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By hybridization and special sexual reproduction, we sequentially aggregated Zea mays, Zea perennis, and Tripsacum dactyloides in an allohexaploid, backcrossed it with maize, derived self-fertile allotetraploids of maize and Z. perennis by natural genome extraction, extended their first six selfed generations, and finally constructed amphitetraploid maize using nascent allotetraploids as a genetic bridge. Transgenerational chromosome inheritance, subgenome stability, chromosome pairings and rearrangements, and their impacts on an organism's fitness were investigated by fertility phenotyping and molecular cytogenetic techniques genomic in situ hybridization (GISH) and fluorescence in situ hybridization (FISH). Results showed that diversified sexual reproductive methods produced highly differentiated progenies (2n = 35–84) with varying proportions of subgenomic chromosomes, of which one individual (2n = 54, MMMPT) overcame self-incompatibility barriers and produced a self-fertile nascent near-allotetraploid by preferentially eliminating Tripsacum chromosomes. Nascent near-allotetraploid progenies showed persistent chromosome changes, intergenomic translocations, and rDNA variations for at least up to the first six selfed generations; however, the mean chromosome number preferably maintained at the near-tetraploid level (2n = 40) with full integrity of 45S rDNA pairs, and a trend of decreasing variations by advancing generations with an average of 25.53, 14.14, and 0.37 for maize, Z. perennis, and T. dactyloides chromosomes, respectively. The mechanisms for three genome stabilities and karyotype evolution for formatting new polyploid species were discussed.

By hybridization and special sexual reproduction, we sequentially aggregatedZea mays, Zea perennis,andTripsacum dactyloidesin an allohexaploid, backcrossed it with maize, derived self-fertile allotetraploids of maize andZ. perennisby natural genome extraction, extended their first six selfed generations, and finally constructed amphitetraploid maize using nascent allotetraploids as a genetic bridge. Transgenerational chromosome inheritance, subgenomes stability, chromosome pairings and rearrangements, and their impacts on an organism’s fitness were investigated by fertility phenotyping and molecular cytogenetics techniques GISH and FISH. Results showed that diversified sexual reproductive methods produced highly differentiated progenies (2n=35-84) with varying proportions of subgenomic chromosomes, of which one individual (2n=54, MMMPT) overcame self-incompatibility barriers and produced self-fertile nascent near-allotetraploid by preferentially eliminatingTripsacumchromosomes. Nascent near-allotetraploid progenies showed persistent chromosome changes, intergenomic translocations, and rDNA variations for at least up to the first six selfed generations; however, ploidy tended to stabilize at near-tetraploid level (2n=40) with full integrity of 45SrDNA pairs, and a trend of decreasing variations by advancing generations with an average of 25.53, 14.14, and 0.37 maize,Z. perennis,andT. dactyloideschromosomes, respectively. The mechanisms for three genome stabilities and karyotype evolution for formatting new polyploid species were discussed.

Summary Low-temperature chilling injury in early spring or late spring severely restricts maize production. Therefore, improving its temperature tolerance is one of the important goals of maize breeding. The wild maize relatives such as Z. perennis and T. dactyloides have strong cold tolerance and thus can be used to improve the cold tolerance of cultivated maize. In the previous study, the allohexaploid MTP ( Zea . Z. perennis and T. dactyloides ) was created as a genetic bridge material and the introgressed cross of the backbone maize inbred line to obtain the MTP-maize introgression line with strong cold tolerance. In this study, F 2:3 populations was developed of the cold-tolerant maize introgression line IB030 and the cold-sensitive maize introgression line IB021. A high-density genetic linkage map was constructed using SSR genetic markers and performed QTL mapping for related traits at 2°C, RNA-seq was performed using cold-tolerant introgression line IB030 and recurrent parent B73 (cold-sensitive) after low temperature stress at seedling stage. The key genes controlling REC, SDW and SFW of maize introgression line seedlings were located by forward genetics combined with WGCNA analysis strategy. Key genes function verification results showed that, Zm00001d037590 REC and Zm00001d012321 REC have the highest expression levels in introgression line IB030, followed by the wild type B73, and finally the EMS mutant after low temperature stress, these results initially concluded that key genes positively regulate the cold tolerance of maize, and also laid a theoretical and practical foundation for improvement of cultivated maize against low-temperature stress.

In recommendation systems, the rating matrix is often very sparse. Collaborative filtering recommendation algorithms cannot be applied to sparse matrices or used in cold start problems. Although the users’ trust relationships provide some useful additional information for recommendation systems, the existing research has not incorporated the rating matrix and trust relationships well. The trust relationship itself also has the problem of data sparsity. With a focus on the problem of sparsity and low accuracy in collaborative filtering algorithms, this paper proposes a general framework, called neural multi-task collaborative filtering (NMCF), which can simultaneously predict the rating and trust relationships. That is, the rating of the same user in e-commerce platforms and the trust relationships in social networks promote and complement each other and help to improve the prediction accuracy of both. The study results for three datasets of real-world show that our algorithm performs better in recommendation, and the accuracy of the proposed algorithm is significantly improved compared with that of the comparison models.

A trispecific hybrid, MTP (hereafter called tripsazea), was developed from intergeneric crosses involving tetraploid Zea mays (2n = 4x = 40, genome: MMMM), tetraploid Tripsacum dactyloides (2n = 4x = 72, TTTT), and tetraploid Z. perennis (2n = 4x = 40, PPPP). On crossing maize-Tripsacum (2n = 4x = 56, MMTT) with Z. perennis, 37 progenies with varying chromosome numbers (36-74) were obtained, and a special one (i.e., tripsazea) possessing 2n = 74 chromosomes was generated. Tripsazea is perennial and expresses phenotypic characteristics affected by its progenitor parent. Flow cytometry analysis of tripsazea and its parents showed that tripsazea underwent DNA sequence elimination during allohexaploidization. Of all the chromosomes in diakinesis I, 18.42% participated in heterogenetic pairing, including 16.43% between the M- and P-genomes, 1.59% between the M- and T-genomes, and 0.39% in T- and P-genome pairing. Tripsazea is male sterile and partly female fertile. In comparison with previously synthesized trihybrids containing maize, Tripsacum and teosinte, tripsazea has a higher chromosome number, higher seed setting rate, and vegetative propagation ability of stand and stem. However, few trihybrids possess these valuable traits at the same time. The potential of tripsazea is discussed with respect to the deployment of the genetic bridge for maize improvement and forage breeding.

In this study, the chromosome number and composition of a novel perennial forage crop, 'Yucao No. 6' (Yu6), was revealed by chromosome spread and McGISH (multicolor genomic in situ hybridization) techniques to clarify its genitor origin. Cytogenetic analysis showed that Yu6, which has 56 chromosomes, is an aneuploid representing 12, 17 and 27 chromosomes from Zea mays ssp. mays L. (Zm, 2n = 2x = 20), Tripsacum dactyloides L. (Td, 2n = 4x = 72), and Z. perennis (Hitchc.) Reeves & Mangelsd. (Zp, 2n = 4x = 40), respectively. This finding indicates that Yu6 is the product of a reduced egg (n = 36 = 12Zm + 17Td + 7Zp) of MTP (a near-allohexaploid hybrid, 2n = 74 = 20Zm + 34Td + 20Zp) fertilized by a haploid sperm nucleus (n = 20Zp) of Z. perennis. Moreover, 3 translocated chromosomes consisting of the maize-genome chromosome with the segment of Z. perennis were observed. These results suggest that it is practical to develop perennial forage maize by remodeling the chromosomal architecture of MTP offspring with Z. perennis as a pollen parent. Finally, the overview of forage breeding in the Zea and Tripsacum genera was discussed.

Background: Helictotrichon Virescens is a perennial herb mainly distributed in high altitude areas of 2000 ~ 4500 m. It is widely cultivated in the Qinghai-Tibet Plateau of China, strongly resistant to cold, and an essential part of wild herbage in this region. However, the molecular mechanism of Helictotrichon virescens response to low-temperature stress is unclear, and the key regulating genes to specific biological processes are poorly known. Results: It was used physiological and transcriptome analysis to study the cold stress response mechanism in Helictotrichon Virescens. Under low-temperature treatment at 0℃, the leaves reduced chlorophyll content and light energy absorption through light antenna complex (LHCs). As the content of chlorophyll, a and b decreased, as evident were the photoprotection effects. Besides, circadian pathway-plant is crucial for the response to cold stress in Helictotrichon Virescens. Among them, DEG encoding LHY and HY5 showed strongly up-regulated expression during cold stress in Helictotrichon Virescens. Conclusions: This study provides an opportunity to fully understand the response process of Helictotrichon Virescens to low-temperature stress. It answers the pertinent questions in perennial herbaceous cold stress research, how leaves integrate light and low-temperature signals to regulate circadian rhythms in crops, and how leaf tissue reduces light absorption and enhances light protection through optical antenna complex (LHCs).

Background Helictotrichon virescens is a perennial grass that is primarily distributed in high altitude areas of 2000 ~ 4500 m. It is widely cultivated in the Qinghai-Tibet Plateau of China, strongly resistant to cold, and an essential part of the wild herbs in this region. However, the molecular mechanism of the response of H. virescens to low temperature stress and the key regulatory genes for specific biological processes are poorly understood. Results Physiological and transcriptome analyses were used to study the cold stress response mechanism in H virescens. During the low temperature stress period, the content of chlorophyll a and b decreased more and more with the delay of the treatment time. Among them, the difference between the controls was not significant, and the difference between the control and the treatment was significant. At the same time, the expression of related differential genes was up-regulated during low temperature treatment. In addition, the plant circadian pathway is crucial for their response to cold stress. The expression of differentially expressed genes that encode LHY and HY5 were strongly up-regulated during cold stress. Conclusions This study should help to fully understand how H. virescens responds to low temperatures. It answers pertinent questions in the response of perennial herbs to cold stress, i.e., how light and low temperature signals integrate to regulate plant circadian rhythms and Decrease of content of chlorophylls (which can be also accompanied with decrease of total quantity of reaction centers) leads to an increase in photosynthetic damage.

In this study, the chromosome number and composition of a novel perennial forage crop, ‘Yucao No. 6’ (Yu6), was revealed by chromosome spread and McGISH (multicolor genomic in situ hybridization) techniques to clarify its genitor origin. Cytogenetic analysis showed that Yu6, which has 56 chromosomes, is an aneuploid representing 12, 17 and 27 chromosomes from Zea mays ssp. mays L. (Zm, 2n = 2x = 20), Tripsacum dactyloides L. (Td, 2n = 4x = 72), and Z. perennis (Hitchc.) Reeves & Mangelsd. (Zp, 2n = 4x = 40), respectively. This finding indicates that Yu6 is the product of a reduced egg (n = 36 = 12Zm + 17Td + 7Zp) of MTP (a near-allohexaploid hybrid, 2n = 74 = 20Zm + 34Td + 20Zp) fertilized by a haploid sperm nucleus (n = 20Zp) of Z. perennis. Moreover, 3 translocated chromosomes consisting of the maize-genome chromosome with the segment of Z. perennis were observed. These results suggest that it is practical to develop perennial forage maize by remodeling the chromosomal architecture of MTP offspring with Z. perennis as a pollen parent. Finally, the overview of forage breeding in the Zea and Tripsacum genera was discussed.

In order to overcome the problem of low throughput and time-consuming of traditional fingerprint minutiae matching methods, a new convolutional-deep neural network is proposed for parallel fingerprint minutiae matching. This method realises the preprocessing of the initial image through four steps: normalisation, image enhancement, parallel thinning and image segmentation. The convolutional-deep neural network is constructed from convolution kernel, convolution layer, pooling layer and full connection layer to extract minutiae of fingerprint image. Through feature minutiae matching, local matching and global matching, the matching results of fingerprint parallel nodes are obtained. The experimental results show that compared with the traditional matching method, the fingerprint matching throughput of convolutional-deep neural network is increased by 25%, and the matching time is saved by about 8 seconds.

Tripsacum dactyloides is closely related to Zea mays since Zea perennis and the MTP tri- species hybrid have four possible reproductive modes. Eastern gamagrass (Tripsacum dactyloides L.) and tetraploid perennial teosinte (Zea perennis) are well known to possess genes conferring resistance against biotic and abiotic stresses as well as adaptation to flood and aluminum toxic soils. However, plant breeders have been hampered to utilize these and other beneficial traits for maize improvement due to sterility in their hybrids. By crossing a tetraploid maize-inbred line × T. dactyloides, a female fertile hybrid was produced that was crossed with Z. perennis to yield a tri-genomic female fertile hybrid, which was backcrossed with diploid maize to produce BC1 and BC2. The tri-genomic hybrid provided a new way to transfer genetic material from both species into maize by utilizing conventional plant breeding methods. On the basis of cytogenetic observations using multi-color genomic in situ hybridization, the progenies were classified into four groups, in which chromosomes could be scaled both up and down with ease to produce material for varying breeding and genetic purposes via apomixis or sexual reproduction. In the present study, pathways were found to recover maize and to obtain specific translocations as well as a speedy recovery of the T. dactyloides–maize addition line in a second backcross generation. However, phenotypes of the recovered maize were in most cases far from maize as a result of genetic load from T. dactyloides and Z. perennis, and could not be directly used as a maize-inbred line but could serve as an intermediate material for maize improvement. A series of hybrids was produced (having varying chromosome number, constitution, and translocations) with agronomic traits from all three parental species. The present study provides an application of overcoming the initial interspecific barriers among these species. Moreover, T. dactyloides is closely related to Z. mays L. ssp. mays since Z. perennis and the MTP tri- species hybrid have four possible reproductive modes.

This study was aimed to investigate the stability of chromosomes during meiosis in autopolyploid and allopolyploid maize, as well as to determine an association of chromosomes between maize (Zeamaysssp.mays Linnaeus, 1753) andZ.perennis(Hitchcock, 1922) Reeves & Mangelsdor, 1942, by producing a series of autopolyploid and allopolyploid maize hybrids. The intra-genomic and inter-genomic meiotic pairings in these polyploids were quantified and compared using dual-color genomic in-situ hybridization. The results demonstrated higher level of chromosome stability in allopolyploid maize during meiosis as compared to autopolyploid maize. In addition, the meiotic behavior ofZ.perenniswas relatively more stable as compared to the allopolyploid maize. Moreover, ten chromosomes of "A” subgenome in maize were homologous to twenty chromosomes ofZ.perennisgenome with a higher pairing frequency and little evolutionary differentiation. At the same time, little evolutionary differentiation has been shown by chromosomes of "A” subgenome in maize, while chromosomes of "B” subgenome, had a lower pairing frequency and higher evolutionary differentiation. Furthermore, 5IM+ 5IIPP+ 5IIIMPPand 5IIMM+ 5IIPP+ 5IVMMPPwere observed in allotriploids and allotetraploids respectively, whereas homoeologous chromosomes were found between the "A” and "B” genome of maize andZ.perennis.

Allopolyploidization plays the special role in the evolution of many crops. Moreover, the evolution in early stage of some allopolyploidization events is predicted to be effected by nuclear-cytoplasmic interactions. Maize and teosintes are well model system for study of genetic recombination in allopolyploidization. In order to investigate the effects of genome organization and cytoplasm on genome evolution in newly synthesized allopolyploids (neoallopolyploids), a series of neoallopolyploids were produced by reciprocal crosses of maize and Zea perennis. By using dual-color genomic in situ hybridization, intra- and intergenomic meiosis pairing of these polyploids were quantified and compared with regard to its genome organization and cytoplasm background. In the four neoallopolyploids, the stability of maize genome is consistently lower than that of Z. perennis genome. Additional, the stability of maize genome is affected by genome ploidy. The cytoplasm, genome composition and their interaction do have the special role in chromosome paring and the meiosis behaviors in Zea allopolyploids vary significantly and showed non-diploidization. Z. perennis cytoplasm may give a relatively relaxed environment for maize genome.

Hybridization, which allows for gene flow between crops, is difficult between maize and Zea perennis. In this study, we aim to initiate and study gene flow between maize and Z. perennis via a special aneuploid plant (MDT) derived from an interspecific hybrid of the two species. The chromosome constitution and morphological characters of MDT as well as certain backcross progenies were examined. Results from genomic in situ hybridization (GISH) indicate that aneuploid MDT consisted of nine maize chromosomes and 30 Z. perennis chromosomes. The backcross progenies of MDT×maize displayed significant diversity of vegetative and ear morphology; several unusual plants with specific chromosome constitution were founded in its progenies. Some special perennial progeny with several maize chromosomes were obtained by backcrossing MDT with Z. perennis , and the first whole chromosome introgression from maize to Z. perennis was detected in this study. With this novel material and method, a number of maize-tetraploid teosinte addition or substitution lines can be generated for further study, which has great significance to maize and Z. perennis genetic research, especially for promoting introgression and transferring desirable traits.

Aim: The aim of this study was to develop a modified rat model for postpartum stress urinary incontinence (SUI) which can be easily established and which will steadily evaluate urodynamic changes. Material and Methods: A urinary catheter was placed into the vaginas of rats (n = 40) and the balloon was inflated for 8 h to simulate labor. A whisker was inserted into the nostril to induce sneezing. The urodynamic changes induced by vaginal dilation or sneezing were observed by measurement of leak point pressure (LPP), and maximum bladder volume. Serum lactose dehydrogenase (LDH) and creatine kinase (CK) were tested, and the mRNA expression of caspase-3 in pubococcygeus muscle tissue was measured to show the effect of muscle injury in SUI. Results: After 8 h of balloon vaginal dilation, a rat model of postpartum SUI was established with a success rate of 72.5% (29/40). By sneeze assay, SUI was noted in 100% (5/5), 80% (4/5), 60% (3/5), 60% (3/5) and 40% (2/5) of experimental rats on day 1, 7, 14, 28 and 56, respectively. No SUI was found in the control group (n = 10). The level of serum LDH and CK in these 29 experimental rats initially increased, peaked on day 7, and finally decreased toward normal values. Compared with control rats, the differences were significant (P

Human papillomavirus 58 (HPV58) is one type of HPV with high risk of causing cervical cancer. Unusually high prevalence of HPV58 has been reported in Asia, Africa and some other areas. However, due to the scattered distribution of global data, in addition to the lack of data of some HPV58 high-incidence nations and regions, like Mainland China, a comprehensive analysis of the global geographical distribution of HPV58 remains blank so far. In this study, HPV58 from the human cervical cancer tissue was detected in Mainland China, and 14 new HPV58-E6/L1 gene sequences were obtained. Moreover, phylogeographic analysis has been conducted combining the HPV58 sequences that have been deposited in GenBank since 1985. The study result shows that the sequences detected from the Shanghai, Jiangsu and Sichuan areas are homologous with those found in the past from Hong Kong and Xi'an, China, as well as Japan and other Southeast Asian areas. Furthermore, Western Africa is considered to be the "root" source of the HPV58 variant, while Mainland China and Southeast Asia are "transit points" and the new sources of HPV58 after receiving the isolates from the "root" source; like HPV16 and HPV18, the HPV58 might also be one of the major HPV types associated with the development and spread of cervical cancer.

Chemotherapy is an important treatment for ovarian cancer. However, conventional chemotherapy has inevitable drawbacks due to side effects from nonspecific biodistribution of the chemotherapeutic drugs. To solve such problem, targeted delivery approaches were developed. The targeted delivery approaches combine drug carriers with the targeting system and can preferentially bring drugs to the targeted sites. Follicle-stimulating hormone receptor (FSHR) is an ovarian cancer–specific receptor. By using a peptide derived from FSH (amino acids 33–53 of the FSH β chain, named as FSH33), we developed a conjugated nanoparticle, FSH33-NP, to target FSHR in ovarian cancer. FSH33-NP was tested for recognition specificity and uptake efficiency on FSHR-expressing cells. Then, the antitumor efficiency of paclitaxel (PTX)-loaded FSH33-NP (FSH33-NP-PTX) was determined. FSH33-NP-PTX displayed stronger antiproliferation and antitumor effects compared with free PTX or naked PTX-loaded nanoparticles (NP-PTX) both in vitro and in vivo. In summary, this novel FSH33-NP delivery system showed very high selectivity and efficacy for FSHR-expressing tumor tissues. Therefore, it has good potential to become a new therapeutic approach for patients with ovarian cancer. [Cancer Res 2009;69(16):6506–14]

This paper represents a series of online monitoring data from a 500kV bushing on a converter station's transformer. An online monitoring system with a novel tgd measuring method has been successfully used for bushing tgd supervision. Long term data acquisition is evaluated for the insulation integrity of the bushing. It shows that bushing tgδ depends on its temperature/voltage intersect influence during operation. The largest bushing tgd occurred at the highest voltage and the lower temperatures. A further study of the temperature/voltage intersect influence on bushings need to be scheduled.

Inducible nitric oxide synthase (iNOS) is the key enzyme in NO synthesis and exhibits a high expression in numerous types of malignant tumors. Previous studies have demonstrated that iNOS promotes the production of tumor blood vessels by catalyzing the synthesis of additional NO. Certain experimental evidence has suggested that iNOS may regulate the levels of vascular endothelial growth factor (VEGF), as the level of VEGF may be induced by iNOS during endothelial cell migration and angiogenesis. In this study, it was observed that SiHa and HeLa cells exhibit depressed proliferation levels following the knockdown of iNOS with a lentivirus. In addition, NO levels demonstrated a correlation with VEGF levels in the cell culture supernatant.

The aim of this study was to develop a modified rat model for postpartum stress urinary incontinence (SUI) which can be easily established and which will steadily evaluate urodynamic changes. A urinary catheter was placed into the vaginas of rats (n=40) and the balloon was inflated for 8 h to simulate labor. A whisker was inserted into the nostril to induce sneezing. The urodynamic changes induced by vaginal dilation or sneezing were observed by measurement of leak point pressure (LPP), and maximum bladder volume. Serum lactose dehydrogenase (LDH) and creatine kinase (CK) were tested, and the mRNA expression of caspase-3 in pubococcygeus muscle tissue was measured to show the effect of muscle injury in SUI.After 8 h of balloon vaginal dilation, a rat model of postpartum SUI was established with a success rate of 72.5% (29/40). By sneeze assay, SUI was noted in 100% (5/5), 80% (4/5), 60% (3/5), 60% (3/5) and 40% (2/5) of experimental rats on day 1, 7, 14, 28 and 56, respectively. No SUI was found in the control group (n=10). The level of serum LDH and CK in these 29 experimental rats initially increased, peaked on day 7, and finally decreased toward normal values. Compared with control rats, the differences were significant (P0.05). The expression of the caspase-3 gene in pubococcygeal muscle of experimental rats peaked on day 1 and decreased thereafter, while no such change was seen in the control group, and the difference was significant (P0.05). Eight hours of vaginal balloon dilation resulted in SUI in this rat model. The alterations in serum LDH and CK, and in the muscle's apoptotic genes mimic those observed in human postpartum SUI patients. It can therefore be considered as a useful animal model for the study on the pathogenesis of postpartum SUI.

To enhance the first swing stability a DBF neural network fastvalving controller is proposed. The solution approach is based on a recent fuzzy fastvalving control scheme. Disturbances in the PS are used for training the NN controller. The performance of the DBF neural controller is simulated in a single machine to an infinite bus power system.

A one-step S(N)Ar(H) reaction has been used for the synthesis of photostable probe , which has good water solubility and low cytotoxicity; this probe can be used for targeted imaging of tumour cells by virtue of specific binding between integrin alpha(v)beta(3) and an arginine-glycine-aspartic acid tripeptide sequence.