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After more than 10-years of abandonment, deepwater oilfield M was redeveloped by using four horizontal wells with 800 to 1700 m long sections. The target was the thick, porous sandstone reservoir N with the strong bottomwater drive, which had been intensively produced for 12 years with the horizontal wells placed at the middle part of the original oil column (15 to 42 m height). The local interbeds with poor properties within the reservoir were proved insufficient to block the water breakthrough. Consequently, the new horizontal sections were planned at the upper section of the clean reservoir with more than 10-m standoff to the uncertain oil/water contact (OWC) and enough distance to offset drilled boreholes. However, uncertainties from the reservoir properties, fluid characterization, and structural dip greatly complicated the effective oil trap profile and the further important well placement strategy. Global successful cases and modeling results pushed the decision team to use an ultradeep reservoir mapping service (UDRMS) to cost-effectively optimize this redevelopment efficiency. With the depth-of-investigation (DOI) up to 30 m from the borehole, UDRMS could use the resistivity inversion to remotely and certainly detect multiple boundaries and map the properties details of this specific thick reservoir, including the reservoir top, local interbeds’ boundaries, OWC, and the intricate layering of contrasting resistivity within the reservoir. These certain and quantitative details could combine the conventional petrophysical logging data to effectively manage related uncertainties and then strategically instruct the productive drilling in the horizontal section for the expected well performance. The successful redevelopment results validated the effective contributions from the UDRMS certain products. Along the long sections up to 1685 m, all uncertain elements were accurately ascertained. Within a corridor of approximately 100 m centered on the wellbore, up to five boundaries were mapped vertically to reveal the certain details of properties, reservoir top, and OWC. The dynamic OWC was identified as still tilted even after a long-term production shutdown and the remaining oil columns were higher than 12 m. Within the actual downdip structural framework, the smooth horizontal trajectories were placed in the upper reservoir with the quantitative distance to reservoir top and tilted OWC, while avoiding the local zones with poor properties. Even at the structural low, the special strategy was executed to guarantee the minimum 10 m standoff above OWC. The well placement efficiency satisfied the redevelopment requirements to positively affect the well performance. As a game-changing enabler, UDRMS-derived certain products displayed their advantages for cost-effectively managing the uncertainties affecting the development of the thick reservoirs with the diverse complexities.

Improving the accuracy, speed and flexibility of the space reconnaissance system are the major challenges facing the current remote sensing application. In this paper, considering the shortcomings of single optical remote sensing satellite, an intelligent reconnaissance system includes two satellites is designed. A semi-physical simulation system is designed and implemented to verify the principle. A YOLO-based method is used to realize the rapid detection of model ship in simulation system. The results of object detection is used as input for load decision algorithm to guide the system to carry out detailed investigation and continuous tracking to the target area.

Aiming at the problem of positioning and tracking of near-space hypersonic vehicles, the tracking performance of low-track binary satellite system based on space-based infrared satellites is explored. According to the established equation of motion of hypersonic vehicles, the actual ballistic data of the target is obtained based on Matlab simulation, based on STK. The simulation software sets the motion trajectory of the target and the positioning and tracking observation scene of the binary star for the target aircraft. The positioning and tracking algorithm based on aerodynamic model is explored. Combined with the Cubature Kalman filter, the positioning and tracking performance of the model is simulated. The simulation results show that the model has good tracking performance for the jump-gliding ballistic hypersonic vehicle.

Combining ability analysis is commonly used to obtain information for designing more efficient hybrid breeding strategies in rice. However, genetic basis of combining ability is less studied. Two hundred and twenty eight testcross combinations developed by crossing 57 introgression lines derived from two donor parents with four types of widely used male sterile lines were used to conduct combining ability analysis and dissect the genetic basis of combining ability for grain yield and eight related traits. The variances of general combining ability (GCA) and special combining ability (SCA) for all nine traits were highly significant in both years. A total of 32 and 45 main effect QTL controlling GCA and SCA for the nine traits were identified across the two years, respectively. Only six QTL were commonly identified for GCA and SCA. Twenty one of the GCA QTL had the positive alleles from the recurrent parent, Shuhui527. Only 11 and six QTL were commonly detected in the two years, and in the two populations classified by the donor parents, respectively. As for SCA, 22 out of the 45 QTL were commonly identified in the two years and 25 QTL had positive effects. A total of 92 epistatic QTL pairs for GCA were identified. The Shuhui527 alleles at the markers RM508 and RM587 on chromosome 6 had the largest effects on GCA for GY and thus played important roles in making Shuhui527 a key parent in hybrid rice breeding. The ZDZ057 alleles at markers RM4584 on chromosome 7 and RM224 on chromosome 11 could be used to further improve GY GCA of Shuhui527.

Satellite attitude control system is an important subsystem that ensures the normal operation of the satellite. Aiming at the problem that the model-based fault detection method relies on modeling accuracy, an actuator fault detection method based on neural network observer is proposed. The neural network is trained with the error back propagation algorithm including a correction term to ensure the accuracy and weight bounded. The neural network is used to identify and estimate actuator failure. The stability of the observer is proved by Lyapunov method. Simulation results show that this method can effectively detect and estimate actuator failure.

In this paper, a novel small target detection algorithm based on robust master analysis (RPCA) is proposed to solve the problem of small target difficult to detection in single infrared image. Because of the background matrix is a low rank matrix and the target matrix is a sparse matrix, small target detection can be formulated as an optimization problem of recovering low-rank and sparse matrices. RPCA method is used to restore the background matrix and targets matrix, and then choose the inexact augmented Lagrange multipliers to solve RPCA model which is faster. At last, two simulation experiments result indicate that can adapt to a variety of single image and the timeliness is good for small matrix.

Rice is an important food crop worldwide. Genomic research on global germplasm has theoretical and practical significances in the mining of favorable alleles and on genome-based molecular breeding, which are related to Chinese and global food security. Through the 3000 (3K) Rice Genome Project, we collected single nucleotide polymorphism (SNP) and insertion and deletion (InDel) genomic variation data for the 2859 rice genomes, and establish a comprehensive SNP and InDel sub-database for the Rice Functional Genomics-based Breeding (RFGB) Database. This sub-database is a global resource containing a polymorphism information retrieval function, a genome browser visualization system and a data export system for specific genomic regions, along with other tools. This study establishes an important platform for rice gene functional research and rice molecular breeding by genomic selection.

Drought is a major abiotic threat in rice production; thus, there is a need to develop adaptable rice varieties that can withstand drought stress and still produce high yield in non-stressed environments. Green Super Rice (GSR) cultivars address this issue. These cultivars are bred through an innovative introgression breeding strategy that requires less irrigation water and chemical inputs without compromising grain quality and yield. This study verified the physiological efficiency and performance of newly developed GSR cultivars that previously showed favorable response to drought during advanced yield trials. Five drought-tolerant GSR cultivars and two checks were subjected to continuously flooded (CF) and drought-stressed environments during the dry seasons of 2011 and 2012 at the International Rice Research Institute (IRRI) experimental farms in Los Banos, Philippines. The cultivars’ ability to allocate assimilates and accumulate biomass under drought stress during the reproductive stage was verified. Leaf area index (LAI), biomass dry weight, and panicle yield were measured at the panicle initiation (PI), flowering (FL), and physiological maturity (PM) of the sample cultivars. All the cultivars performed satisfactorily in the CF environment with grain yield ranging from 5 to 11.5 tons ha −1 . Water stress during the reproductive stage significantly reduced grain yield by 75–88% in the moderate drought (soil water tension between 100 and 300 kPa in upper 15 cm soil layer) and 77–96% in the severe drought (soil water tension >300 kPa in upper 15 cm soil layer) experiments. The shortened reproductive duration mainly contributed to the significant reduction in yield under drought stress. Two GSR cultivars, GSR IR1-5-S10-D1-D1 and IR83142-B-19-B, responded well in severe drought environments, with grain yield almost similar to the drought check (1.79 tons ha −1 ). Under moderate drought stress, there was a relative yield advantage of 25% and 40% for the two GSR cultivars over the drought check, respectively. Yield advantage across environments, varying from fully irrigated to drought-stressed, was 31–36%. These two GSR cultivars were effective in mobilizing stored carbohydrates from the vegetative organs to the panicles and not shortening the duration from flowering to maturity, to allow all reserved carbohydrates be allocated to storage organs as a mechanism to cope with drought stress. Lower leaf area index (LAI), which allowed balanced biomass accumulation and lower transpiration, without a significant decrease in grain filling duration, was another drought-coping strategy. These physiological responses and characteristics apparently enabled the GSR cultivars to withstand drought stress; these are key indicators for varietal selection in drought-prone environments, particularly in severe drought stress in the reproductive stage. Despite the poor ability of some cultivars to cope with severe drought, three out of five selected GSR cultivars produced grain yield (2.0–2.9 tons ha −1 ) that was the same or higher than the drought check in moderate drought stress. The introgression breeding technique applied in the newly developed drought-tolerant cultivars through the GSR breeding strategy was found to be effective. It could produce high yields in both CF and water-limited environments, and thus, it could serve as a model for other breeding programs to adopt.

Simplified scheme for application of Ho-LAMap to rice. (a) We cross diverse founder varieties (i.e., variety that is significantly different to the reference parent on grain traits) with reference parent (usually has small grain). The founder varieties are deep sequenced by the second-generation sequencing platforms, as in Additional file 30: Figure S30. In several crosses that have detected targeted QTL, the majority of SNPs between the QTL interval will segregate in a 1:1 founder varieties:reference parent ratio. However, the SNP responsible for the change of phenotype is the same in all founder parents, which can detect the targeted QTL. If we define the Ho (observed heterozygosity per locus) index as the ratio between the number of heterozygous crosses corresponding to each SNP locus and the total number of crosses which have detected targeted QTL, we expect this index would equal 1 near the causal SNP and 0.5 for the unlinked loci. (b, d) Candidate region association mapping. The brown horizontal dashed lines indicate the genome-wide significance threshold. The red points indicate significant loci within candidate gene. (c) Ho index plots for the target QTL. Red regression lines were obtained by averaging SNP indices from a sliding window analysis. (PDF 105 kb)

Comparison of GWAS of grain length in the full population using LM model (a), CMLM model (b), and GLM (Q) model (c). In these Manhattan plots, for the significant loci identified, known loci are shown in red. Blue horizontal solid lines indicate the genome-wide significance threshold. (PDF 114 kb)

Frequency distribution of grain length in the mini core collection (MCC population). (PDF 117 kb)

QTL detected in the four crosses derived from six varieties. (a) Distribution of grain shape QTL and genes on genetic linkage map. Blue strip refers to grain length QTL, green to 1000-grain weight and grain width QTL, red to grain thickness QTL and arrows to cloned genes. (b) Heat map for effect of grain length QTL mapped by four linkage populations. Rows of the heat map correspond to the 14 QTL for grain length. NIP, Nipponbare; SLG, SLG-1; CQ, Chuanqi; YF, Yuefu; IR109, IRAT109; HBK, Haobuka. (PDF 224 kb)

Size of association regions about GS3, TGW6, GW8, and OsLG3. Manhattan plots in candidate region of three known genes and OsLG3 in different models. The red points indicate their SNPs within gene region, respectively. The horizontal full lines indicate the genome-wide significance threshold (0.05/n). (PDF 311 kb)

Effect of Q structure (indica and japonica) for grain length. (a) Comparison of grain length between big-grain-haplotype and small-grain-haplotype when Q structure exists. (b) Comparison of grain length between big-grain-haplotype and small-grain-haplotype when the phenotype variation from Q structure was removed. Ind, indica; jap, japonica. Data are means ± SEM. Letters indicate a significant difference at P

Notes S1. Natural population and linkage mapping (Additional file 2: Figure S2 and Additional file 11). Notes S2. Fine mapping of qGL3-3 (Additional file 10). Notes S3. Ho-LAMap â a potential method for validating association peak. Table S2. Summary of the taxa and source of 506 varieties of Oryza sativa L. Table S3. Environments used to evaluate association and linkage populations. Table S4. The heritability of grain traits in MCC1 Panel. Table S9. Summary of causal allele and type of variation about several grain size genes. Table S10. Grain phenotypes of six different parents. Table S11. Quantitative trait loci mapped in the four populations. Table S12. Simulation reveals the cross number need for several known genes (such as TGW6, GS3) about grain size when using Ho-LAMap. Table S13. OsLG3 polymorphisms associated with grain length in the MCC panel. Table S14. Comparison of polymorphisms between three large grain parents and three small grain parents. Table S16. Primers used for fine mapping and sequencing. Table S17. Primers used for DNA constructs and transcript analysis. (DOCX 73 kb)

Correlation between grain length and population structure in the natural population and frequency distribution between two genotypes in subpopulation about GS3, GS5, TGW6, GW8, and OsLG3. (a) Distribution of germplasms with different grain length according to PC structure. (b) Frequency distribution between two genotypes in subpopulation about GS3, GS5, TGW6, GW8, and OsLG3. The rate of each haplotype under two sub population divided by Q for these genes. Ind, indica; jap, japonica. (PDF 246 kb)

Frequency distribution of variation of grain traits in biparental populations derived from NIP and SLG. (aâ d) Phenotype variants of grain traits for populations 07DH010, 07DH011, 07DH013, and 07DH014, respectively. (PDF 103 kb)

Grains from six parents. Scale bar, 5Â mm. (PDF 109 kb)

Wnt-modulator in surface ectoderm (WISE) is a secreted modulator of Wnt signaling expressed in the adult kidney. Activation of Wnt signaling has been observed in renal transplants developing interstitial fibrosis and tubular atrophy; however, whether WISE contributes to chronic changes is not well understood. Here, we found moderate to high expression of WISE mRNA in a rat model of renal transplantation and in kidneys from normal rats. Treatment with a neutralizing antibody against WISE improved proteinuria and graft function, which correlated with higher levels of β-catenin protein in kidney allografts. In addition, treatment with the anti-WISE antibody reduced infiltration of CD68(+) macrophages and CD8(+) T cells, attenuated glomerular and interstitial injury, and decreased biomarkers of renal injury. This treatment reduced expression of genes involved in immune responses and in fibrogenic pathways. In summary, WISE contributes to renal dysfunction by promoting tubular atrophy and interstitial fibrosis.

Here we analyse genetic variation, population structure and diversity among 3,010 diverse Asian cultivated rice (Oryza sativa L.) genomes from the 3,000 Rice Genomes Project. Our results are consistent with the five major groups previously recognized, but also suggest several unreported subpopulations that correlate with geographic location. We identified 29 million single nucleotide polymorphisms, 2.4 million small indels and over 90,000 structural variations that contribute to within- and between-population variation. Using pan-genome analyses, we identified more than 10,000 novel full-length protein-coding genes and a high number of presence–absence variations. The complex patterns of introgression observed in domestication genes are consistent with multiple independent rice domestication events. The public availability of data from the 3,000 Rice Genomes Project provides a resource for rice genomics research and breeding., Analyses of genetic variation and population structure based on over 3,000 cultivated rice (Oryza sativa) genomes reveal subpopulations that correlate with geographic location and patterns of introgression consistent with multiple rice domestication events.

Background Most agronomic traits in rice are complex and polygenic. The identification of quantitative trait loci (QTL) for grain length is an important objective of rice genetic research and breeding programs. Results Herein, we identified 99 QTL for grain length by GWAS based on approximately 10 million single nucleotide polymorphisms from 504 cultivated rice accessions (Oryza sativa L.), 13 of which were validated by four linkage populations and 92 were new loci for grain length. We scanned the Ho (observed heterozygosity per locus) index of coupled-parents of crosses mapping the same QTL, based on linkage and association mapping, and identified two new genes for grain length. We named this approach as Ho-LAMap. A simulation study of six known genes showed that Ho-LAMap could mine genes rapidly across a wide range of experimental variables using deep-sequencing data. We used Ho-LAMap to clone a new gene, OsLG3, as a positive regulator of grain length, which could improve rice yield without influencing grain quality. Sequencing of the promoter region in 283 rice accessions from a wide geographic range identified four haplotypes that seem to be associated with grain length. Further analysis showed that OsLG3 alleles in the indica and japonica evolved independently from distinct ancestors and low nucleotide diversity of OsLG3 in indica indicated artificial selection. Phylogenetic analysis showed that OsLG3 might have much potential value for improvement of grain length in japonica breeding. Conclusions The results demonstrated that Ho-LAMap is a potential approach for gene discovery and OsLG3 is a promising gene to be utilized in genomic assisted breeding for rice cultivar improvement. Electronic supplementary material The online version of this article (doi:10.1186/s12915-017-0365-7) contains supplementary material, which is available to authorized users.

Three populations with a total of 125 BC2F3:4 introgression lines (ILs) selected for high yields from three BC2F2 populations were used for genetic dissection of rice yield and its related traits. The progeny testing in replicated phenotyping across two environments and genotyping with 140 polymorphic simple sequence repeat markers allowed the identification of 21 promising ILs that had significantly higher yields than the recurrent parent Shuhui527 (SH527). A total of 94 quantitative trait loci (QTL) were identified using the selective introgression method based on Chi-squared (χ2) and multi-locus probability tests and the RSTEP-LRT method based on stepwise regression. These QTL were mostly mapped to 12 clusters on seven rice chromosomes. Several important properties of the QTL affecting grain yield (GY) and its related traits were revealed. The first one was the presence of strong and frequent non-random associations between or among QTL that affect low-heritability traits (GY and spikelet number per panicle, SN) in the ILs with high trait values. Second, beneficial alleles at 88.9 % GY and 75 % SN QTL for increased productivity were from the donors, suggesting that direct phenotypic selection for high yield in our introgression breeding program was a powerful way to transfer beneficial alleles at many loci from the donors into SH527. Third, most QTL were in clusters with large effects on multiple traits, which should be the focal points in further investigations and marker-assisted selection in rice. The majority of the QTL identified were expressed only in one of the environments, suggesting that differential expression of QTL in different environments is the primary genetic basis of genotype × environment interaction. Finally, a large variation in both the direction and magnitude of QTL effects was detected for different donor alleles at seven QTL in the same genetic background and environments. This finding suggests the possible presence of functional diversity among the donor alleles at these loci. The promising ILs and QTL identified provide valuable materials and genetic information for further improving the yield potential of SH527, which is a backbone restorer of hybrid rice in China.

The development of bone-rebuilding anabolic agents for treating bone-related conditions has been a long-standing goal. Genetic studies in humans and mice have shown that the secreted protein sclerostin is a key negative regulator of bone formation. More recently, administration of sclerostin-neutralizing monoclonal antibodies in rodent studies has shown that pharmacologic inhibition of sclerostin results in increased bone formation, bone mass, and bone strength. To explore the effects of sclerostin inhibition in primates, we administered a humanized sclerostin-neutralizing monoclonal antibody (Scl-AbIV) to gonad-intact female cynomolgus monkeys. Two once-monthly subcutaneous injections of Scl-AbIV were administered at three dose levels (3, 10, and 30 mg/kg), with study termination at 2 months. Scl-AbIV treatment had clear anabolic effects, with marked dose-dependent increases in bone formation on trabecular, periosteal, endocortical, and intracortical surfaces. Bone densitometry showed that the increases in bone formation with Scl-AbIV treatment resulted in significant increases in bone mineral content (BMC) and/or bone mineral density (BMD) at several skeletal sites (ie, femoral neck, radial metaphysis, and tibial metaphysis). These increases, expressed as percent changes from baseline were 11 to 29 percentage points higher than those found in the vehicle-treated group. Additionally, significant increases in trabecular thickness and bone strength were found at the lumbar vertebrae in the highest-dose group. Taken together, the marked bone-building effects achieved in this short-term monkey study suggest that sclerostin inhibition represents a promising new therapeutic approach for medical conditions where increases in bone formation might be desirable, such as in fracture healing and osteoporosis.

Rice bacterial leaf blight (BB) caused by Xanthomonasoryzae pv. oryzae and bacterial leaf streak (BLS) caused by X. oryzae pv. oryzicola (Xoc) are two important diseases of rice that often outbreak simultaneously and constrain rice production in much of Asia and parts of Africa. Developing resistant cultivars has been the most effective approach to control BB, however, most single resistance genes have limited value in breeding programs because of their narrow-spectrum of resistance to the races of the pathogen. By contrast, there is little progress in breeding varieties resistant to Xoc since BLS resistance in rice was a quantitative trait and so far only a few quantitative resistance loci have been identified. We reported here the development of a high yield elite line, Lu-You-Zhan highly resistant to both BB and BLS by pyramiding Xa23 with a wide-spectrum resistance to BB derived from wild rice and a non-host maize resistance gene, Rxo1, using both marker assisted selection (MAS) and genetic engineering. Our study has provided strong evidence that non-host R genes could be a valuable source of resistance in combating those plant diseases where no single R gene controlling high level of resistance exists and demonstrated that MAS combined with transgenic technologies are an effective strategy to achieve high level of resistance against multiple plant diseases.

Plant photosynthetic traits such as net photosynthetic rate (Pn), stomata conductance (gs), transpiration rate (Tr), and intercellular CO2 concentration (Ci), are known to relate to drought tolerance in plants, but the genetic basis of these traits remains largely uncharacterized because of the difficulty in phenotyping physiological traits in a large mapping population. In this study, a set of 55 overlapping introgression lines (ILs) in the Teqing (indica) background were used to genetically dissect several morph-physiological traits and their relationship with grain yield under water stress and non-stress conditions. These traits included specific leaf weight (SLW), chlorophyll content (CC), leaf stomata frequency (SF), Pn, gs, Tr, and Ci. A total of 40 QTLs affecting the measured traits were identified and mapped to 21 genomic regions in the rice genome. Clustered QTLs affecting Pn, gs, Tr, and Ci in the same genomic regions suggest common genetic bases for the physiological traits. Low or no phenotypic correlations between leaf morphological traits and photosynthetic traits and between morph-physiological traits and grain yield (GY) appeared to be due to inconsistence in QTL effect for clustered QTLs, unlinked QTLs affecting different traits, and to possible epistasis that could not be adequately addressed in this study. Our results indicate that improving drought tolerant (DT) of rice by selecting any single secondary traits is not expected to be effective and the identified QTLs for GY and related morph-physiological traits should be carefully confirmed before to be used for improving DT in rice by MAS.

Drought tolerance (DT) in rice is known to be controlled by many quantitative trait loci (QTLs) and involved differential expression of large numbers of genes, but linking QTLs with their underlying genes remains the most challenging issue in plant molecular biology. To shed some light on this issue, differential gene expression in response to PEG simulated drought in 3 unique genetic materials (a lowland rice, IR64 and its derived line, PD86 which has 11 introgressed DT QTLs, and a upland rice IRAT109) was investigated using a PCR-based subtractive hybridization strategy. More than 300 unique subtracted cDNA sequences, covering genes of diverse cellular activities and functions, were identified and confirmed by semi-quantitative and quantitative RT-PCR. Detailed bioinformatics analyses of the data revealed two interesting results. First, the levels and mechanisms of DT of the three rice lines were associated with the number and types of differentially expressed genes, suggesting different DT mechanisms in rice are controlled by different sets of genes and different metabolic pathways, and most differentially expressed genes under drought were able to contribute to DT. Second, there appeared a high correspondence in genomic location between DT QTLs and clusters of differentially expressed genes in rice, suggesting some DT QTLs may represent clusters of co-regulated and functionally related genes. Thus, differential gene expression analyses using genetically characterized materials can provide additional insights into the molecular basis of QTLs and convergent evidence to shortlist the candidate genes for target QTLs.

A large-scale backcross breeding project has been undertaken to improve drought tolerance in rice. Over 160 donor cultivars from 25 countries have been used in this project, representing a significant proportion of the genetic variation in cultivated rice. These cultivars were evaluated in field experiments in the Philippines to assess their responses to drought in terms of plant height, heading date, and grain yield. Drought was imposed near heading stage, in experiments that were established either in lowland (anaerobic) fields or upland (aerobic) soil. Despite the poor adaptation of some cultivars to the tropics, it was possible to identify significant variation in plant response to drought treatments, and contrasting effects on flowering delay and growth. Subsequently, 325 BC2F2 bulk populations, developed by backcrossing many of these donors to one of three elite recurrent parents, were screened under drought in lowland or upland nurseries. Stress levels were managed to eliminate almost all seed set in recurrent parents, and those progeny that produced grain were selected as being putatively drought-tolerant. The selection intensity varied across years and in selection environments with more severe stress, higher selection intensity could be imposed. The number of plants selected within a population was not associated with the per se drought response of the donors in the direct evaluation, indicating the wide presence of cryptic genetic variation for drought tolerance in the apparently drought-susceptible cultivars. The genetic background of the recurrent parent affected the number of plants selected, as did the selection environment (upland versus lowland nurseries). These drought-selected introgression lines represent a useful genetic resource to develop improved cultivars for farmers in rainfed or water-scarce rice-growing regions, and also to improve our understanding of the genetic and molecular basis of drought tolerance in rice. Genetic analysis of the selected lines, reported elsewhere, indicated specific regions of high introgression. Yield evaluations of the selected lines are now underway across a range of drought scenarios.

Low and unstable rice productivity in many areas of Asia is associated with many abiotic and biotic stresses such as drought, salinity, anaerobic conditions during germination, submergence, phosphorus and zinc deficiency, etc. To develop rice varieties with tolerance to these stresses, we undertook a large backcross (BC) breeding effort for the last 6 years, using three recurrent elite rice lines and 203 diverse donors, which represent a significant portion of the genetic diversity in the primary gene pool of rice. Significant progress has been made in the BC breeding program, which resulted in development of large numbers ofintrogression lines with improved tolerance to these stresses. Promising lines have been developed with excellent tolerances (extreme phenotypes) to salinity, submergence and zinc deficiency; resistance to brown plant hopper, ability to germinate under the anaerobic condition and low temperature. Our results indicated that there exist tremendous amounts of ‘hidden’ diversity for abiotic and biotic stress tolerances in the primary gene pool of rice. Furthermore, we demonstrated that despite the complex genetics and diverse physiological mechanisms underlying the abiotic stress tolerances, introgression of genes from a diverse source of donors into elitegenetic backgrounds through BC breeding and efficient selection (careful screening under severestress) is a powerful way to exploit this hidden diversity for improving abiotic stress tolerances of rice. We have developed three large sets of introgression lines, which not only provide an unique platform of breeding materials for developing new rice cultivars with superior yield and stability by trait/gene pyramiding, but also represent unique genetic stocks for a large-scale discovery of genes/alleles underlying the abiotic and biotic stress tolerances of rice using genomic tools. # 2005 Elsevier B.V. All rights reserved.

A large set of 254 introgression lines in an elite indica genetic background were evaluated for grain yield (GY) and related traits under the irrigated (control) and drought (stress) conditions in two consecutive years for genetic dissection of adaptive strategies of rice to water stress. A total of 36 quantitative trait loci (QTLs) affecting heading date (HD), plant height (PH), GY and yield components were identified and most QTLs showed pronounced differential expression either qualitatively or quantitatively in response to drought. These QTLs could be grouped into three major types based on their behaviors under control and stress conditions. Type I included 12 QTLs that expressed under both the stress and non-stress conditions. Type II comprised 17 QTLs that expressed under irrigation but not under stress. Type III included seven QTLs that were apparently induced by stress. The observation that the Lemont (japonica) alleles at all HD QTLs except QHd5 resulted in early heading under stress appeared to be responsible for the putative adaptation of Lemont to drought by escaping, whereas the Teqing (indica) alleles at most PH/GY QTLs were consistently associated with increased yield potential and trait stability and thus contributed to DT. Our result that most DT QTLs were non-allelic with QTLs for drought escaping suggests that the two adaptive strategies in the parental lines are under possible negative regulation of two largely non-overlapping genetic systems.

Tremendous efforts have been taken worldwide to develop genome-wide genetic stocks for rice functional genomic (FG) research since the rice genome was completely sequenced. To facilitate FG research of complex polygenic phenotypes in rice, we report the development of over 20,000 introgression lines (ILs) in three elite rice genetic backgrounds for a wide range of complex traits, including resistances/tolerances to many biotic and abiotic stresses, morpho-agronomic traits, physiological traits, etc., by selective introgression. ILs within each genetic background are phenotypically similar to their recurrent parent but each carries one or a few traits introgressed from a known donor. Together, these ILs contain a significant portion of loci affecting the selected complex phenotypes at which allelic diversity exists in the primary gene pool of rice. A forward genetics strategy was proposed and demonstrated with examples on how to use these ILs for large-scale FG research. Complementary to the genome-wide insertional mutants, these ILs opens a new way for highly efficient discovery, candidate gene identification and cloning of important QTLs for specific phenotypes based on convergent evidence from QTL position, expression profiling, functional and molecular diversity analyses of candidate genes, highlights the importance of genetic networks underlying complex phenotypes in rice that may ultimately lead to more complete understanding of the genetic and molecular bases of quantitative trait variation in rice.

Estimation of T-lymphocyte subsets continues to be an important aspect for monitoring HIV disease progression and response to antiretroviral therapy. Most of the diagnostic laboratories often rely on studies from western for CD4+T-lymphocyte reference values, which could, often be unreliable for usage in local settings. To establish the normal reference values of T lymphocyte subsets from healthy people of Inner Mongolia Autonomous Region, flow cytometry was performed to determine the reference ranges for lymphocyte subsets (CD3 and CD4 cells) in 400 healthy multiracial adult population from 12 League Cities in Inner Mongolia Region, China. The basic information including age, gender, nationality and history was collected. There were significant differences in the absolute counting, percentage of CD3+T lymphocytes, and CD4+T lymphocyte percentage counting among different age groups. There were significant differences in CD3+, CD4+T lymphocyte percentage in the groups with different genders. There were significant differences in CD3+T lymphocyte percentage count, absolute count of CD4+T lymphocytes and CD4+T lymphocyte percentage counting in the group with ages of 16-20. There were dramatic differences in CD3+T lymphocyte percentage count and CD4+T lymphocyte percentage counting in the group with ages of 31-40. There were significant differences in CD4+T lymphocyte percentage counting. By this study, age, gender and ethnic specific lymphocyte subset reference ranges have been locally established in Inner Mongolia Autonomous Region.

The Green Revolution (GR-I) included worldwide adoption of semi-dwarf rice cultivars (SRCs) with mutant alleles at GA20ox2 or SD1 encoding gibberellin 20-oxidase. Two series of experiments were conducted to characterize the pleiotropic effects of SD1 and its relationships with large numbers of QTLs affecting rice growth, development and productivity. The pleiotropic effects of SD1 in the IR64 genetic background for increased height, root length/mass and grain weight, and for reduced spikelet fertility and delayed heading were first demonstrated using large populations derived from near isogenic IR64 lines of SD1. In the second set of experiments, QTLs controlling nine growth and yield traits were characterized using a new molecular quantitative genetics model and the phenotypic data of the well-known IR64/Azucena DH population evaluated across 11 environments, which revealed three genetic systems: the SD1-mediated, SD1-repressed and SD1-independent pathways that control rice growth, development and productivity. The SD1-mediated system comprised 43 functional genetic units (FGUs) controlled by GA. The SD1-repressed system was the alternative one comprising 38 FGUs that were only expressed in the mutant sd1 backgrounds. The SD1-independent one comprised 64 FGUs that were independent of SD1. GR-I resulted from the overall differences between the former two systems in the three aspects: (1) trait/environment-specific contributions; (2) distribution of favorable alleles for increased productivity in the parents; and (3) different responses to (fertilizer) inputs. Our results suggest that at 71.4 % of the detected loci, a QTL resulted from the difference between a functional allele and a loss-of-function mutant, whereas at the remaining 28.6 % of loci, from two functional alleles with differentiated effects. Our results suggest two general strategies to achieve GR-II (1) by further exploiting the genetic potential of the SD1-repressed and SD1-independent pathways and (2) by restoring the SD1-mediated pathways, or ‘back to the nature’ to fully exploit the genetic diversity of those loci in the SD1-mediated pathways which are virtually inaccessible to most rice-breeding programs worldwide that are exclusively based on sd1.

This paper focus on the high frequency of conflict and complex constraints in ground TT&C(Tracking Telemetering and Command) resources scheduling problems. A detailed analyze of resources and requests has been made. Tasks are divided into collections of requests classified by their phases with a sequent based on constraint to describe their logic. Six constraints including equipment matching constraint, time windows constraint, antenna confliction constraint, satellite competition, sequential logic constraint and consumable resource constraint are particularly expressed. To meet the vary preferences from usage of resources to accomplishment of requests by different users, three heuristic principals have been added to the CSP(Constraints Satisfaction Problem) model. In the end of this paper, the model is validated by a simulation.