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The abundance of domesticated sheep varieties and phenotypes is largely the result of long-term natural and artificial selection. However, there is limited information regarding the genetic mechanisms underlying phenotypic variation induced by the domestication and improvement of sheep. In this study, to explore genomic diversity and selective regions at the genome level, we sequenced the genomes of 100 sheep across 10 breeds and combined these results with publicly available genomic data from 225 individuals, including improved breeds, Chinese indigenous breeds, African indigenous breeds, and their Asian mouflon ancestor. Based on population structure, the domesticated sheep formed a monophyletic group, while the Chinese indigenous sheep showed a clear geographical distribution trend. Comparative genomic analysis of domestication identified several selective signatures, including IFI44 and IFI44L genes and PANK2 and RNF24 genes, associated with immune response and visual function. Population genomic analysis of improvement demonstrated that candidate genes of selected regions were mainly associated with pigmentation, energy metabolism, and growth development. Furthermore, the IFI44 and IFI44L genes showed a common selection signature in the genomes of 30 domesticated sheep breeds. The IFI44 c. 54413058 C>G mutation was selected for genotyping and population genetic validation. Results showed that the IFI44 polymorphism was significantly associated with partial immune traits. Our findings identified the population genetic basis of domesticated sheep at the whole-genome level, providing theoretical insights into the molecular mechanism underlying breed characteristics and phenotypic changes during sheep domestication and improvement. [ABSTRACT FROM AUTHOR]

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Even though high-quality X- and gamma rays with photon energy below mega-electron volt (MeV) are available from large-scale X-ray free electron lasers and synchrotron radiation facilities, it remains a great challenge to generate bright gamma rays over 10 MeV. Recently, gamma rays with energies up to the MeV level were observed in Compton scattering experiments based on laser wakefield accelerators, but the yield efficiency was as low as 10-6, owing to low charge of the electron beam. Here, we propose a scheme to efficiently generate gamma rays of hundreds of MeV from submicrometer wires irradiated by petawatt lasers, where electron accelerating and wiggling are achieved simultaneously. The wiggling is caused by the quasistatic electric and magnetic fields induced around the wire surface, and these are so high that even quantum electrodynamics (QED) effects become significant for gamma-ray generation, although the driving lasers are only at the petawatt level. Our full 3D simulations show that directional, ultrabright gamma rays are generated, containing 1012 photons between 5 and 500 MeV within a 10-fs duration. The brilliance, up to 1027 photons s-1 mrad-2 mm-2 per 0.1% bandwidth at an average photon energy of 20 MeV, is second only to X-ray free electron lasers, while the photon energy is 3 orders of magnitude higher than the latter. In addition, the gamma ray yield efficiency approaches 10%-that is, 5 orders of magnitude higher than the Compton scattering based on laser wakefield accelerators. Such high-energy, ultrabright, femtosecond-duration gamma rays may find applications in nuclear photonics, radiotherapy, and laboratory astrophysics. [ABSTRACT FROM AUTHOR]

Objectives: This study explored the correlation between clinical explorations, including modified Mallampati score and Müller's maneuver, with drug-induced sleep endoscopy (DISE) findings regarding retrolingual obstruction. Methods: One hundred forty-two obstructive sleep apnea patients were enrolled in this prospective study. All of the patients received clinical explorations including modified Mallampati scoring and Müller's maneuver in the clinic. Druginduced sleep endoscopy was further evaluated in the operating room. Results: A significant relationship was noted between modified Mallampati score and retrolingual obstruction during DISE. In contrast, no significant relationship was noted between Müller's maneuver and DISE findings regarding retrolingual obstruction. Conclusions: A significant discrepancy existed between retrolingual airway collapse evaluated by modified Mallampati score and Müller's maneuver. Modified Mallampati score is more correlated with DISE regarding retrolingual obstruction compared to Müller's maneuver. It should therefore be used as an initial evaluation of retrolingual obstruction when DISE is unavailable. [ABSTRACT FROM AUTHOR]

Objective: Coscinium fenestratum belongs to the family of Menispermaceae. It is a woody plant that originated from Indomalaya regions such as southern India, Sri Lanka, Thailand, Vietnam, Cambodia, and West Malaysia. C. fenestratum has been reported to possess various pharmacological actions such as antioxidant, antiproliferative, antidiabetic, and antibacterial activities. In addition, this medicinal plant has also been used to treat gastrointestinal disorders, including ulcer. The purified fractions A-E of dichloromethane (DCM) extract obtained from the stem of C. fenestratum were investigated for antioxidant activity and its ability to protect the gastric mucosa against hydrochloric acid (HCl)/ethanol, nonsteroidal anti-inflammatory drugs (NSAIDs), and stress-induced ulcer. The bioactive compounds were identified using high-performance liquid chromatography (HPLC) and simple biochemical screening. Methods: Air-dried stem extract was soaked in DCM to obtain crude extract which was purified using column chromatography. HPLC and basic biochemical screening were used to identify the bioactive compound present. HCl/ethanol induced, NSAIDs, and stress of animal were used to induce gastric ulcer. The rats were orally administered with purified A-E extract for gastroprotective and antioxidant activity. Results: The oral administration of fractions A-E exhibited gastroprotective activity by reducing the ulcerative index induced by HCl/ethanol, NSAIDs, and stress compared to saline. The extract showed high antioxidant effect, especially fraction E. The HPLC and phytochemical analysis of fraction E showed the presence of palmatine and flavonoid. Conclusion: The extract showed a very strong gastroprotective and antioxidant activities and the highest activity was observed by fraction E. The activity may be because of the presence of palmatine and flavonoid. [ABSTRACT FROM AUTHOR]

Background: Global trend of the introduction of high levels of relatively cheap carbohydrates to reduce the amount of costly protein in the aquatic animal feed production has affected the aquaculture of an economically important cyprinid fish, blunt snout bream (Megalobrama amblycephala). This dietary shift has resulted in increased prevalence of metabolic disorders, often causing economic losses. High dietary intake of carbohydrates, associated with obesity, is one of the major causes of non-alcoholic fatty liver disease (NAFLD) in humans. Results: We have conducted an eight-week feeding trial to better understand how a high-carbohydrate diet (HCBD) affects the liver health in this fish. Hepatosomatic index and lipid content were significantly (P < 0.05) higher in the HCBD group. Histology results also suggested pathological changes in the livers of HCBD group, with excessive lipid accumulation and indication of liver damage. Metabolomics and serum biochemistry analyses showed that a number of metabolites indicative of liver damage were increased in the HCBD group. This group also exhibited low levels of betaine, which is a metabolite crucial for maintaining the healthy liver functions. Transcriptomic and qPCR analyses indicated that HCBD had a strong impact on the expression of a large number of genes associated with the NAFLD and insulin signalling pathways, which may lead to the development of insulin resistance in hepatocytes, pathological liver changes, and eventually the NAFLD. Conclusions: Transcriptomics, metabolomics and histology results all indicate early symptoms of liver damage. However whether these would actually lead to the development of NAFLD after a longer period of time, remains inconclusive. Additionally, a very high number of upregulated genes in the HCBD group associated with several neurodegenerative diseases is a strong indication of neurodegenerative changes caused by the high-carbohydrate diet in blunt snout bream. This suggests that fish might present a good model to study neurodegenerative changes associated with high-carbohydrate diet in humans. [ABSTRACT FROM AUTHOR]

To study Megalobrama amblycephala adaption to water hypoxia, the changes in physiological levels, innate immune responses, redox balance of M.amblycephala during hypoxia were investigated in the present study. When M. amblycephala were exposed to different dissolved oxygen (DO) including control (DO: 5.5mg/L) and acute hypoxia (DO: 3.5 and 1.0mg/L, respectively), hemoglobin (Hb),methemoglobin (MetHb), glucose, Na+, succinatedehydrogenase (SDH), lactate, interferon alpha (IFNα), and lysozyme (LYZ), except hepatic glycogen and albumin gradually increased with the decrease of DO level. When M. amblycephala were exposed to different hypoxia time including 0.5 and 6 h (DO: 3.5mg/L), and then reoxygenation for 24 h after 6 h hypoxia, Hb, MetHb, glucose, lactate, and IFNα, except Na+, SDH, hepatic glycogen, albumin, and LYZ increased with the extension of hypoxia time, while the above investigated indexes (except albumin, IFNα, and LYZ) decreased after reoxygenation. On the other hand, the liver SOD, CAT, hydrogen peroxide (H2O2), and total ROS were all remained at lower levels under hypoxia stress. Finally, Hif-1α protein in the liver, spleen, and gill were increased with the decrease of oxygen concentration and prolongation of hypoxia time. Interestingly, one Hsp70 isoforms mediated by internal ribozyme entry site (IRES) named junior Hsp70 was only detected in liver, spleen and gill. Taken together, these results suggest that hypoxia affects M. amblycephala physiology and reduces liver oxidative stress. Hypoxia-reoxygenation stimulates M. amblycephala immune parameter expressions, while Hsp70 response to hypoxia is tissue-specific. [ABSTRACT FROM AUTHOR]

Single nucleotide polymorphisms (SNPs) are the most dominant type of DNA variations in genome which is useful in genetic linkage mapping and quantitative traits loci analysis. In this study, a SNP's database of blunt snout bream (Megalobrama amblycephala) was obtained from the transcripts of cDNA library using Solexa/Illumina sequencing. A total of 36,326 putative SNPs were discovered from the transcripts. One SNP was found in 29.2 base pair length of the transcripts. The transition and transversion mutation was 21,445 and 12,553 SNPs, respectively. A ratio of transition to transversion was 1.71. Within those yielded SNPs, 10,812 SNPs identified from 2,421 unigenes could be annotated to differential functionality in comparing to public database using BLASTX for gene ontology (GO), eukaryotic orthologous groups of proteins (KOG), and Kyoto encyclopedia of genes and genomes (KEGG). A number of SNPs (n = 7,727, 71.5%) found from 1,628 unigenes were assigned to three main GO categories: 'cellular components', 'molecular function' and 'biology process'. In total, 5,812 SNPs (53.8%) identified from 1,324 unigenes were classified into 25 KOG categories. 4,589 SNPs (42.4%) detected from 975 unigenes were assigned to 278 KEGG pathways. Furthermore, a number of 600 SNPs found from 111 unigenes were successfully annotated in the term 'immune system' via KEGG classification. The SNP's database in this study could be useful for further genetic studies in blunt snout bream. [ABSTRACT FROM AUTHOR]

Background: Intermuscular bones (IBs) and ribs both are a part of skeletal system in teleosts, but with different developing process. The chemical composition of fish IBs and ribs as well as the underlying mechanism about their development have not been investigated. In the present study, histological structures showed that one bone cavity containing osteoclasts were existed in ribs, but not in IBs of Megalobrama amblycephala. We constructed the first proteomics map for fish bones including IBs and ribs, and identified the differentially expressed proteins between IBs and ribs through iTRAQ LC-MS/MS proteomic analysis. Results: The proteins extracted from IBs and ribs at 1- to 2-year old M. amblycephala were quantified 2,342 proteins, with 1,451 proteins annotated with GO annotation in biological processes, molecular function and cellular component. A number of bone related proteins as well as pathways were identified in the study. A total of 93 and 154 differently expressed proteins were identified in comparison groups of 1-IB-vs-1-Rib and 2-IB-vs-2-Rib, which indicated the obvious differences of chemical composition between these two bone tissues. The two proteins (vitronectin b precursor and matrix metalloproteinase-2) related to osteoclasts differentiation were significantly upregulated in ribs compared with IBs (P < 0.05), which was in accordance with the results from histological structures. In comparison groups of 1-IB-vs-2-IB and 1-Rib-vs-2-Rib, 33 and 51 differently expressed proteins were identified and the function annotation results showed that these proteins were involved in regulating bone development and differentiation. Subsequently, 11 and 13 candidate proteins in comparison group of 1-IB-vs-1-Rib and 1-IB-vs-2-IB related to bone development were validated by MRM assays. Conclusions: Our present study suggested the different key proteins involved in the composition of fish ribs and IBs as well as their growth development. These findings could provide important clues towards further understanding of fish skeletal system and the roles of proteins playing in regulating diverse biological processes in fish. [ABSTRACT FROM AUTHOR]

Interleukin 10 (IL-10) is important in the inflammatory cytokine mechanisms of many organisms. This study describes the identification and characterisation of the IL-10 homolog obtained from transcriptome profile of blunt snout bream Megalobrama amblycephala Yih 1955 (Cyprinidae): MaIL-10. It contained an ORF of 534 bp encoding a putative protein of 177 amino acids. MaIL-10 protein contained a conserved IL10 family domain. Physicochemical characterisation analysis revealed that it was soluble, basic, hydrophilic, unstable based on the instability index, and thermostable based on its aliphatic index. Alpha helix (56.50%) was predominant among the secondary structure elements, followed by random coil (25.42%), extended strand (12.43%) and beta turn (5.65%), while the remaining elements were absent. MaIL-10 3-D model was generated by comparative modelling using a human IL-10-like (PDB ID: 1lqs.1.D) as the template. The acceptable model was validated using Procheck's Ramachandran plot, ProQ and ProSA-web tools. Immune challenge of blunt snout bream with Aeromonas hydrophila bacterium (1.8x105 cfu fish-1) demonstrated a significant differences in the expression of maIL-10 in liver, spleen and kidney within 120 h post-infection (P<0.01). The results of this study indicate that maIL-10 plays an important role in the innate immune system of blunt snout bream. [ABSTRACT FROM AUTHOR]

Seismology plays an important role in characterizing potential underground nuclear tests. Using broad-band digital seismic data from Northeast China, South Korea and Japan, we investigated the properties of the recent seismic event occurred in North Korea on 2016 January 6. Using a relative location method and choosing the previous 2006 explosion as the master event, the 2016 event was located within the North Korean nuclear test site, with its epicentre at latitude 41.3003°N and longitude 129.0678°E, approximately 900 m north and 500mwest of the previous event on 2013 February 12. Based on the error ellipse, the relocation uncertainty was approximately 70 m. Using the P/S spectral ratios, including Pg/Lg, Pn/Lg and Pn/Sn, as the discriminants, we identify the 2016 event as an explosion rather than an earthquake. The body-wave magnitude calculated from regional wave Lg is mb(Lg) equal to 4.7 ± 0.2. Adopting an empirical magnitude-yield relation, and assuming that the explosion is fully coupled and detonated at a normally scaled depth, we find that the seismic yield is about 4 kt, with the uncertainties allowing a range from 2 to 8 kt. [ABSTRACT FROM AUTHOR]

In this paper, an optical imaging module design for an astigmatic detection system (ADS) is presented. The module is based on a commercial optical pickup unit (OPU) and it contains a coaxial illuminant for illuminating a specimen. Furthermore, the imaging module facilitates viewing the specimen and the detection laser spot of the ADS with a lateral resolution of approximately 1 μm without requiring the removal of an element of the OPU. Two polarizers and one infrared filter are used to eliminate stray laser light in the OPU and stray light produced by the illuminant. Imaging modules designed for digital versatile disks (DVDs) and Blu-ray DVDs were demonstrated. Furthermore, the module can be used for imaging a small cantilever with approximate dimensions of 2 μm (width) × 5 μm (length), and therefore, it has the potential to be used in high-speed atomic force microscopy. [ABSTRACT FROM AUTHOR]

As research topics become increasingly complex, large scale interdisciplinary research projects are commonly established to foster cross-disciplinary cooperation and to utilize potential synergies. In the case of the Collaborative Research Center (CRC) 1026, 19 individual projects from different disciplines are brought together to investigate perspectives and solutions for sustainable manufacturing. Beside overheads regarding the coordination of activities and communication, such interdisciplinary projects are also facing challengs regarding data management. For exchange and combination of research results, data from individual projects have to be stored systematically, categorized, and linked according to the logical interrelations of the involved disciplinary knowledge domains. In the CRC 1026, the project for information infrastructure observed and analysed collaboration practices and developed IT-supported solutions to facilitate and foster research collaboration. Data management measures in this period were mainly focused on building a shared conceptual framework, and the organization of task related data. For the former aspect, an ontology basesd apporach was developed and prototypically implemented. For the latter aspect, a message board integrated task management system was developed and applied. [ABSTRACT FROM AUTHOR]

Hypoxia, a unique and essential environmental stress, evokes highly coordinated cellular responses, and hypoxia-inducible factor (HIF) 1 in the hypoxia signaling pathway, an evolutionarily conserved cellular signaling pathway, acts as a master regulator of the transcriptional response to hypoxic stress. MicroRNAs (miRNAs), a major class of posttranscriptional gene expression regulators, also play pivotal roles in orchestrating hypoxia-mediated cellular adaptations. Here, global miRNA expression profiling and quantitative real-time PCR indicated that the up-regulation of the miR-462/miR-731 cluster in zebrafish larvae is induced by hypoxia. It was further validated that miR-462 and miR-731 are up-regulated in a Hif-1a-mediated manner under hypoxia and specifically target ddx5 and ppm1da, respectively. Overexpression of miR-462 and miR-731 represses cell proliferation through blocking cell cycle progress of DNA replication, and induces apoptosis. In situ detection revealed that the miR-462/miR-731 cluster is highly expressed in a consistent and ubiquitous manner throughout the early developmental stages. Additionally, the transcripts become restricted to the notochord, pharyngeal arch, liver, and gut regions from postfertiliztion d 3 to 5. These data highlight a previously unidentified role of the miR-462/miR-731 cluster as a crucial signaling mediator for hypoxia-mediated cellular adaptations and provide some insights into the potential function of the cluster during embryonic development. [ABSTRACT FROM AUTHOR]

Copper-induced delayed hatching and dysfunctional movement had been reported previously, and unbalanced free copper was found in the body of humans with Alzheimer's disease and other neural diseases, but details of the underlying mechanisms are still unknown. In this study, zebrafish (Danio rerio) embryos exposed to over 3.9 lM of copper-exhibited delayed hatching and significantly dysfunctional movement. Using high-throughput in situ hybridization screening and by conducting an in-depth analysis of gene characterization in embryos exposed to copper, we found that copper caused neural crest defects from the initiation stage of neurogenesis, and embryos younger than the 70% epiboly stage were sensitive to copper toxicity. The myelination of Schwann cells, other than melanophores, cartilage, and neurons, was inhibited by copper during neurogenesis. In addition, axon guidance was blocked by copper. Downregulated cdx4-hox might have contributed to the neurogenesis-related defects. Moreover, copper inhibited the differentiation of muscle fibers and myotomes but not the specification of muscle progenitors. In summary, our data reveal a novel molecular mechanism for copper-inhibited locomotor behavior in embryos, in which copper blocks functional muscle fiber specification during myogenesis and inhibits the specification of axons and Schwann cell myelination during neurogenesis. A combination of these processes results in dysfunctional locomotor behavior in zebrafish embryos exposed to copper. [ABSTRACT FROM AUTHOR]

Background: MicroRNA-124 (miR-124) has been reported to be downregulated in breast cancer. However, its clinical significance and prognostic value in breast cancer have not been extensively studied. Methods: The tissue expression levels of miR-124 were measured using quantitative real-time PCR in 133 breast cancer patients. The correlation between the miR-124 levels and the clinicopathological factors of the patients was also analyzed. Survival and Cox proportional-hazards regression analyses were performed to determine the correlation between miR-124 expression levels and prognosis in the patients. Results: Quantitative real-time PCR analysis showed that miR-124 had lower expression in breast cancer specimens than that in matched adjacent normal breast tissues (0.39 ± 0.16 vs. 1.00 ± 0.39; P < 0.05). Low miR-124 expression level was significantly associated with advanced TNM stage (P = 0.011), lymph node metastasis (P = 0.012), and poorer pathological differentiation (P = 0.023). A significant difference was found that breast cancer patients with low miR-124 expression level had distinctly shorter overall survival than patients with high miR-124 expression level (63.8% vs. 35.2%, P = 0.03). Furthermore, multivariate analysis of the prognosis factors with a Cox proportional hazards model confirmed that low miR-124 expression was a significant independent predictor of poor survival in breast cancer (HR = 3.16, 95% CI: 1.79-9.13, P = 0.017). Conclusion: These findings proved that the decreased expression of miR-124 might be associated with tumor progression and poor prognosis in patients with breast cancer. [ABSTRACT FROM AUTHOR]

MyD88 and TRAF6 play an essential role in the innate immune response in most animals. This study reports the full-length MaMyD88 and MaTRAF6 genes identified from the blunt snout bream (Megalobrama amblycephala) transcriptome profile. MaMyD88 is 2501 base pairs (bp) long, encoding a putative protein of 284 amino acids (aa), including the N-terminal DEATH domain of 78 aa and the C-terminal TIR domain of 138 aa. MaTRAF6 is 2252 bp long, encoding a putative protein of 542 aa, including the N-terminal low-complexity region, RING domain (40 aa), a coiled-coil region (64 aa) and C-terminal MATH domain (147 aa). Coding regions of MaMyD88 and MaTRAF6 genomic sequences consisted of five and six exons, respectively. Physicochemical and functional characteristics of the proteins were analysed. Alpha helices were dominant in the secondary structure of the proteins. Homology models of the MaMyD88 and MaTRAF6 domains were constructed applying the comparative modelling method. RT-qPCR was used to analyse the expression of MaMyD88 and MaTRAF6 mRNA transcripts in response to Aeromonas hydrophila challenge. Both genes were highly upregulated in the liver, spleen and kidney during the first 24 h after the challenge. While MyD88 and TRAF6 have been reported in various aquatic species, this is the first report and characterisation of these genes in blunt snout bream. This research also provides evidence of the important roles of these two genes in the blunt snout bream innate immune system. [ABSTRACT FROM AUTHOR]

Objective: This study aimed to study methods for protecting the language areas during tumor surgery in Mandarin-Cantonese bilinguals (MCBs). Materials and Methods: Eleven MCB patients were positioned for awake surgery with the purpose of preserving both of their language proficiencies. All the exposed cortices were electrically stimulated 1 cm × 1 cm with anelectrode, and all the positive sites of stimulation were recorded for analyses, the tumor resection point was limited by 1cm distant from the language areas identified by electrical stimulation. Results: All patients had at least one language area identified; a total of 154 points were stimulated, with 22 positive points (14.3%), including five specific language areas, which all resulted in simple anomiain either language when stimulated. Among these, three were specific to Mandarin (1.9%), whereas two were specific to Cantonese (1.3%). Conclusions: In proficient MBCs, areas specific to each language exist. Thus, performing intraoperative bilingual tasks to locate these language areas is necessary in order to preserve language function. [ABSTRACT FROM AUTHOR]

We demonstrate that the optical absorption is enhanced in small molecule organic solar cells by using a trapezoid grating structure. The enhanced absorption is mainly attributed to both waveguide modes and surface plasmon modes, which is simulated by using finite-difference time-domain method. The simulated results show that the surface plasmon along the semitransparent metallic Ag anode is excited by introducing the periodical trapezoid gratings, which induce the increase of high intensity field in the donor layer. Meanwhile, the waveguide modes result in a high intensity field in acceptor layer. The increase of field improves the absorption of organic solar cells significantly, which is demonstrated by simulating the electrical properties. The simulated results also show that the short-circuit current is increased by 31% in an optimized device, which is supported by the experimental measurement. Experimental result shows that the power conversion efficiency of the grating sample is increased by 7.7%. [ABSTRACT FROM AUTHOR]

Significant high magnetic gradient field strength is essential to obtaining high-resolution images in a benchtop magnetic resonance imaging (BT-MRI) system with permanent magnet. Extending minimum wire spacing and maximum wire width of gradient coils is one of the key solutions to minimize the maximum current density so as to reduce the local heating and generate higher magnetic field gradient strength. However, maximum current density is hard to optimize together with field linearity, stored magnetic energy, and power dissipation by the traditional target field method. In this paper, a new multi-objective method is proposed to optimize the maximum current density, field linearity, stored magnetic energy, and power dissipation in MRI gradient coils. The simulation and experimental results show that the minimum wire spacings are improved by 159% and 62% for the transverse and longitudinal gradient coil respectively. The maximum wire width increases from 0.5 mm to 1.5 mm. Maximum gradient field strengths of 157 mT/m and 405 mT/m for transverse and longitudinal coil are achieved, respectively. The experimental results in BT-MRI instrument demonstrate that the MRI images with in-plane resolution of 50 μm can be obtained by using the designed coils. [ABSTRACT FROM AUTHOR]

Background Blunt snout bream (Megalobrama amblycephala) is an economically important fish species in the Chinese freshwater polyculture system for its delicacy and high economic value. MicroRNAs (miRNAs) play important roles in regulation of almost all biological processes in eukaryotes. Although previous studies have identified thousands of miRNAs from many species, little information is known for miRNAs of M. amblycephala. To investigate functions of miRNAs associated with growth of M. amblycephala, we adopted the Solexa sequencing technology to sequence two small RNA libraries prepared from four growth related tissues (brain, pituitary, liver and muscle) of M. amblycephala using individuals with relatively high and low growth rates. Results In this study, we have identified 347 conserved miRNAs (belonging to 123 families) and 22 novel miRNAs in M. amblycephala. Moreover, we observed sequence variants and seed edits of the miRNAs. Of the 5,166 single nucleotide substitutions observed in two libraries, the most abundant were G-to-U (15.9%), followed by U-to-C (12.1%), G-to-A (11.2%), and A to G (11.2%). Subsequently, we compared the expression patterns of miRNAs in the two libraries (big-size group with high growth rate versus small-size group with low growth rate). Results indicated that 27 miRNAs displayed significant differential expressions between the two libraries (p < 0.05). Of these, 16 were significantly up-regulated and 11 were significantly down-regulated in the big-size group compared to the small-size group. Furthermore, stem-loop RT-PCR was applied to validate and profile the expression of the differentially expressed miRNAs in ten tissues, and the result revealed that the conserved miRNAs expressed at higher levels than the novel miRNAs, especially in brain, liver and muscle. Also, targets prediction of differentially expressed miRNAs and KEGG pathway analysis suggested that differentially expressed miRNAs are involved in growth and metabolism, signal transduction, cell cycle, neural development and functions. Conclusions The present study provides the first large-scale characterization of miRNAs in M. amblycephala and miRNA profile related to different growth performances. The discovery of miRNA resource from this study is expected to contribute to a better understanding of the miRNAs roles playing in regulating the growth biological processes and the study of miRNA function and phenotype-associated miRNA identification in fish. [ABSTRACT FROM AUTHOR]

Background: It is well documented that cancer cells secrete angiogenic factors to recruit and sustain tumor vascular networks. However, little is known about the effects of endothelial cells on the behavior of tumor cells. The study here was to determine the roles of endothelial cells in HCC cell growth, migration and invasion. Methods: A mixture of highly metastatic MHCC97H cells and HUVEC cells, as well as MHCC97H cells alone were subcutaneously injected into nude mice to observe the effects of HUVECs on HCC growth. The biological characteristics of MHCC97H cells respectively treated with conditioned medium (CM) derived from HUVECs and endothelial cell basal medium (EBM) in vitro, such as proliferation, migration and invasion, invasion/metastasis associated gene expression, were comparatively analyzed. Differential cytokines between CM and EBM were screened and identified using human cytokine array. Effects of the interested differential cytokine CCL2, IL-8 and CXCL16 and its related signaling pathways were further investigated in HCC cells. Results: Subcutaneous tumorigenicity of MHCC97H cells in nude mice was promoted by HUVECs and its invasion/ metastasis associated genes were significantly upregulated. The in vitro, proliferation, migration and invasion of HCC cells treated with CM were all significantly enhanced as compared to those with EBM stimulation. Simultaneously, PI3K/Akt and ERK1/2 pathway in HCC cells were activated by CM. Total of 25 differential cytokines were identified between CM and EBM such as angiopoietin-2, CCL2 (MCP-1), uPA, endostatin, CXCL16, IL-8, pentraxin 3 etc. The selected differential cytokines CCL2, IL-8 and CXCL16 all modulated the expressions of HCC invasion/metastasis genes, especially MMP2 and MMP9. In exposure to CCL2 or CXCL16 alone, upregulation in AKT phosphorylation but no change in ERK phosphorylation were found in MHCC97H cells, moreover the contents of nuclear transcription factor NF-?B were increased as compared to the control. However, no effects on the activation of Akt and ERK pathway in MHCC97H were found in exposure to IL-8. Conclusion: This study expands the contribution of endothelial cells to the progression of HCC. It unveils a new paradigm in which endothelial cells function as initiators of molecular crosstalks that enhance survival, migration and invasion of HCC cells. [ABSTRACT FROM AUTHOR]

Laser absorption in the interaction between ultra-intense femtosecond laser and solid density plasma is studied integratedly for the intensity range Iλ2 1014-1020 W cm-2 µm² by particle-in-cell simulations with collision modulus included. The collisional effect is found to be significant when the incident laser intensity is less than 1016 W cm-2 µm², which tends to enhance the resonance absorption and reduce the vacuum heating under different plasma parameters. At higher intensities, various collisionless absorption mechanisms dominate with a large number of hot electrons produced. The scaling of hot electron temperatures is found to depend upon the dominant absorption mechanisms. At moderate intensity around 1017 W cm-2, the scaling law is Thot ... (Iλ²)1/3 when the incident angle matches the optimized angle of resonance absorption; otherwise, Thot ... (Iλ²)α with α > 1/3, which changes with laser incident angles and preplasma scale lengths; in the case of vacuum heating, usually α > 1. At laser intensity above 1018 W cm-2 µm² when the absorption mechanism is dominated by ponderomotive acceleration, the scaling becomes Thot ... (Iλ²)1/2. The angular distributions of hot electrons are also shown to be dependent upon the absorption mechanisms. [ABSTRACT FROM AUTHOR]

Here we report a high-throughput spinning device for nanometric scale measurements of microstructures with instrumentation details and experimental results. The readout technology implemented in the designed disc-like device is based on a DVD data storage optical pick-up unit (OPU). With a spinning mechanism, this device can simultaneously measure surface topography, mechanical deflections and resonance frequencies of several microfabricated beams at a high speed. In biochemical sensing applications, the OPU can measure bending changes of functionalized microcantilevers, providing a statistically robust and label-free bio-detection analysis of multiple compounds. The signal-to-noise ratio (S/N) is demonstrated from statistical measurements as 1.2 with arginine detection at 750 nM concentration. Practically, the OPU can measure up to 480 individual cantilever sensors per second with nanometer resolution. The opto-mechanical optimization of the device design and settings for biochemical detection are described. [ABSTRACT FROM AUTHOR]

Two-dimensional (2D) nuclear magnetic resonance (NMR) distributions as functions of diffusion coefficient and relaxation time are powerful tools in the study of porous media. We propose a practical method to perform proper truncation of singular value decomposition (TSVD) in Laplace inversion for obtaining 2D-NMR distributions from measured NMR data. By analyzing basic algorithms for Laplace inversion, it is well known that proper TSVD does not affect the inversion result for an ill-posed problem with zero-order Tikhonov regularization, but can greatly increase the inversion speed. In this new method, the optimal number of singular values for data compression is applied to each dimension separately. The method also makes full use of the redundancy nature of the data with a finite signal-to-noise ratio and well balances the tradeoff between the speed and the bias. The method does not require the stochastic information of the estimated parameters when obtaining the optimal number of singular values. [ABSTRACT FROM AUTHOR]

Turbulence in fluids is a ubiquitous, fascinating, and complex natural phenomenon that is not yet fully understood. Unraveling turbulence in high density, high temperature plasmas is an even bigger challenge because of the importance of electromagnetic forces and the typically violent environments. Fascinating and novel behavior of hot dense matter has so far been only indirectly inferred because of the enormous difficulties of making observations on such matter. Here, we present direct evidence of turbulence in giant magnetic fields created in an overdense, hot plasma by relativistic intensity (1018W/cm2) femtosecond laser pulses. We have obtained magneto-optic polarigrams at femtosecond time intervals, simultaneously with micrometer spatial resolution. The spatial profiles of the magnetic field show randomness and their k spectra exhibit a power law along with certain well defined peaks at scales shorter than skin depth. Detailed two-dimensional particle-in-cell simulations delineate the underlying interaction between forward currents of relativistic energy "hot" electrons created by the laser pulse and "cold" return currents of thermal electrons induced in the target. Our results are not only fundamentally interesting but should also arouse interest on the role of magnetic turbulence induced resistivity in the context of fast ignition of laser fusion, and the possibility of experimentally simulating such structures with respect to the sun and other stellar environments. [ABSTRACT FROM AUTHOR]

We present a scheme for proton acceleration from a moving double layer formed by an ultraintense circularly polarized laser pulse with intensity 1021-1023 Wcm-2 irradiated on a combination target. The target is composed of a thin overdense proton-rich foil located at the front followed by an underdense gas region behind with an effective Z/A ratio of the order of 1/3. When the areal density of the thin foil is small enough, the protons together with electrons in the thin overdense foil can be pre-accelerated under the laser irradiation. As the laser pulse passes through the thin foil and propagates in the underdense gas region, it excites high-amplitude electrostatic fields moving at a high speed, which appear like a moving double layer. The pre-accelerated protons can get trapped and accelerated in the moving double layer and tens of GeV quasi-monoenergetic proton beams are achieved, provided the laser intensity and plasma density are properly chosen, as demonstrated by one-dimensional (1D) and 2D particlein- cell (PIC) simulations. [ABSTRACT FROM AUTHOR]

In this paper, by considering energy conservation and the self-gravitation reaction in the dynamical background space-time, we attempt to extend Kerner and Mann's work to the Vaidya–de Sitter black hole by the fermion-tunneling method. The result we derive shows that the tunneling probability of the Vaidya–de Sitter black hole is related not only to the change in the Bekenstein–Hawking entropy but also to the integral of the changing horizon, which are different from the stationary cases. tant donné la conservation de l’énergie et la réaction d’auto-gravité sur un fond dynamique d’espace-temps, nous cherchons à étendre le travail de Mann et Kerner sur le trou noir de Vaidya–de Sitter via l’effet tunnel de fermion. Le résultat que nous obtenons indique que la probabilité d’effet tunnel du trou noir de Vaidya–de Sitter est relié non seulement au changement d’entropie de Bekenstein–Hawking, mais aussi à l’intégrale du changement d’horizon, qui sont différents des cas stationnaires. [ABSTRACT FROM AUTHOR]

The length-weight relationships (LWRs) were determined for five freshwater fish species collected from Liangzi Lake, the Xi River and Longxi River in China, including Megalobrama amblycephala, Megalobrama skolkovii, Megalobrama pellegrini and Megalobrama terminalis belonging to the genus Megalobrama, as well as white Amur bream (Parabramis pekinensis) of the genus Parabramis. Three of these five species had no previous LWR estimates in the FishBase. The LWRs of hybrids from Megalobrama amblycephala ♀ x Parabramis pekinensis ♂ and Megalobrama amblycephala ♀ x Megalobrama terminalis ♂ were also reported for the first time. [ABSTRACT FROM AUTHOR]

The Fourier finite-difference propagator and the generalized-screen propagator are two general high-order forms of one-way dual-domain methods. We compare these two propagators mainly on phase accuracy, computational efficiency and 3D extension. A comparison of phase accuracy shows that the high-order generalized-screen propagator is preferable to the Fourier finite-difference propagator for heterogeneous media with a weak velocity contrast and wide dip angle. With increasing velocity contrast, the accuracy improvement gained by the high-order generalized-screen propagator declines rapidly. The Fourier finite-difference propagator is more robust and flexible to lateral velocity variations than the generalized-screen propagator. The 2D Fourier finite-difference propagator is superior to the 2D generalized-screen propagator when the velocity contrast is stronger than 23%. Despite the two-way splitting error, the 3D Fourier finite-difference propagator is more accurate than the second-order generalized-screen propagator when the velocity contrast is stronger than 20% and is more accurate than the fourth-order generalized-screen propagator when the velocity contrast is stronger than 40%. Numerical experiments on the SEG/EAGE salt model demonstrate that the Fourier finite-difference propagator behaves better than the generalized-screen propagator when imaging steep salt boundary and faults beneath the salt body. Under the same hardware and software conditions, the computational cost of the Fourier finite-difference propagator in our implementation is greater than that of the second-order generalized-screen propagator but smaller than that of the third-order generalized-screen propagator. Compared with the Fourier finite-difference propagator, the generalized-screen propagator requires fewer grid points per wavelength and has more potential to improve running speed in the presence of a much faster Fourier transform. These analyses are applicable for both forward modelling and depth migration. [ABSTRACT FROM AUTHOR]

Conventional two-way splitting Fourier finite-difference migration for 3D complex media yields azimuthal anisotropy where an additional phase correction is needed with much increase of computational cost. We incorporate the alternating-direction-implicit plus interpolation scheme into the conventional Fourier finite-difference method to reduce azimuthal anisotropy. This scheme retains the high-order remnants ignored by the two-way splitting in the form of a wavefield interpolation in the wavenumber domain. The wavefield interpolation for each step of downward extrapolation is implemented between the wavefields before and after the conventional Fourier finite-difference extrapolation. As the Fourier finite-difference migration is implemented in the space and wavenumber dual space, the Fourier transforms between space and wavenumber domain that were needed for the alternating-direction-implicit plus interpolation in frequency domain (FD) migration are saved in Fourier finite-difference migration. Since the azimuth anisotropy in Fourier finite-difference is much less than that in FD, the application of the alternating-direction-implicit plus interpolation scheme in Fourier finite-difference migration is superior to that in FD migration in handling complex media with large velocity contrasts and steep dips. Impulse responses show that the presented method reduces the azimuthal anisotropy at almost no extra cost. [ABSTRACT FROM AUTHOR]

The propagation of asymmetric relativistic intense laser beams in nonuniform and uniform underdense cold plasmas is studied. After simplifying the wave equation, we obtain the evolution equation of the transverse centroid of laser beams in terms of variational approaches. Theoretical analysis shows that in uniform plasmas a laser beam with an asymmetric initial phase has a constant centroid drift velocity, at which the centroid of the laser beam drifts away from the light axis in a fixed direction; the centroid drift velocity of a laser beam with symmetric initial phase, but either symmetric or asymmetric amplitude, is always zero, i.e., the symmetric features of the laser field is retained. Furthermore, the channel-like symmetric plasma plays a role like a restoring force to confine the laser centroid around the density channel axis so the centroid of the laser beam with asymmetric amplitude or phase is going to oscillate with damp around the channel axis. The nonlinear effect can symmetrize initially asymmetric laser beams and the steeper effective density gradient is more beneficial to the symmetrizing process. Finally, the analytic results are checked and confirmed by numerical simulations with finite difference to the wave equation and two-dimensional particle-in-cell code. [ABSTRACT FROM AUTHOR]

Titanium diboride was calculated by the density function and discrete variational (DFT-DVM) method to study the relation between structure and properties. Titanium and its first-nearest boron atoms form a strong covalent bond, so TiB2 has high melting point, hardness and chemical stability. Titanium atom releases two electrons to form Ti2+ ions, and a boron atom gets one electron to come into B− ion. B− takes the sp2 hybrid and forms σ bonds to link other boron atoms in the same layer. The other one 2pz orbital of every B− ion in the same layer interacts each other to form the π molecular orbital, so TiB2 has fine electrical property. The calculated density of state is close to the result of XPS experiment of TiB2. Mainly Ti3d and B2p atomic orbitals contribute the total DOS near the Fermi level. [ABSTRACT FROM AUTHOR]

Examines the mean field upper and lower bounds Lyapunov exponents. Discussions regarding supersymmetric field theories; Details on the mean field rate of decay for squared Green's functions at the critical energy; Information on Grassmann variables.

A suitable combustion synthesis and densification process was designed to fabricate dense NiAl/TiB2 composites from Ni−Al−Ti−B system. Combustion synthesis processing and microstructure characteristics of products were studied in detail. The results show that the amount of TiB2 ceramics has a great influence on the combustion synthesis processing and microstructure; with the increase of the amount of TiB2 ceramics, the combustion temperature and combustion velocity increase rapidly. The volume of synthesized products and the grain size of ceramics particle size are also affected by the amount of TiB2 ceramics. TiB2 ceramics fiber can be produced in this synthesis system. The dense NiAl/TiB2 composites with residual porosity of no more than 1% are fabricated by the combustion synthesis and hot pressing, the mechanical properties of the dense NiAl/TiB2 composites increase with increase of the amount of TiB2 ceramics. [ABSTRACT FROM AUTHOR]

We propose a new single-shot method for measuring terahertz pulses using a linearly chirped optical pulse interferogram. Modulated frequency domain phase information can be extracted by the interferogram recorded on imaging spectrographs. The terahertz pulse waveform is obtained from the phase information. We overcome the energy fluctuation problem by using the phase information, making a reference shot unnecessary and the terahertz detection more flexible and convincing. [ABSTRACT FROM AUTHOR]

Terahertz radiation generated by focusing the fundamental laser pulse and its second harmonic into ambient air strongly saturates with increasing pump laser energy. We demonstrate a simple method to control the Gaussian pump laser beam to improve the output of terahertz radiation with an adjustable aperture. With the optimal aperture-limited pump laser beams, the terahertz wave amplitudes can be enhanced by more than eight times depending on the pump laser parameters than those of aperture-free cases. [ABSTRACT FROM AUTHOR]