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Cultural heritage management poses significant challenges for museums due to fragmented data, limited intelligent frameworks, and insufficient applications. In response, a digital cultural heritage management approach based on knowledge graphs and deep learning algorithms is proposed to address the above challenges. A joint entity-relation triple extraction model is proposed to automatically identify entities and relations from fragmented data for knowledge graph construction. Additionally, a knowledge completion model is presented to predict missing information and improve knowledge graph completeness. Comparative simulations have been conducted to demonstrate the effectiveness and accuracy of the proposed approach for both the knowledge extraction model and the knowledge completion model. The efficacy of the knowledge graph application is corroborated through a case study utilizing ceramic data from the Palace Museum in China. This method may benefit users since it provides automated, interconnected, visually appealing, and easily accessible information about cultural heritage. [ABSTRACT FROM AUTHOR]

First-principles calculations are performed to inspect the electronic and transport properties of a Fe-thiacrown molecular device, namely, a Au-Fe(9S3)2-Au junction. It is found that the junction has a low-spin (LS) ground state and a high-spin (HS) metastable state. Further study shows that the HS state is a conducting state while the LS state is a nearly insulating one, which means that a switch between these two spin configurations results in a good electrical switching behavior and can serve as an ON/OFF state for a logic unit. Thus, it may find applications as switches or memories in molecular electronic circuits. [ABSTRACT FROM AUTHOR]

Due to the adverse operational environment, submarine pipelines are susceptible to the development of free spans under pipes, which may endanger the integrity of entire pipeline systems and subsequently inflict huge economic losses and huge costs to restore ecological conditions. To maintain the integrity of pipeline systems, it is very important to develop an effective and reliable approach to identify and localise free-spanning damage at an early stage. In this study, the influence of different bedding conditions on modal parameters of submarine pipelines is first systematically investigated by considering the subsea operational environment. Then, the feasibility of curvatures of lower-frequency mode-shapes for localising free-spanning damage of pipelines is discussed, and damage indicators based on mode-shape curvatures are proposed. Numerical simulations are conducted on a 100 m long pipeline to illustrate how to localise free-spanning damage using the proposed damage indicators. The efficacy of the proposed damage indicators is validated by experimental tests. [ABSTRACT FROM AUTHOR]

Abstract. Objective:  Atherosclerosis is considered as a chronic inflammatory response in arterial blood vessels. The function of osteopontin (OPN), a proinflammatory cytokine, in the Ang II-induced inflammatory activation in vascular smooth muscle cells (VSMCs) remains poorly understood. Methods:  In the present study, the role of OPN was investigated by knocking down OPN using small interfering RNA (siRNA). VSMCs from human saphenous vein were divided into three groups according to RNAi treatment: OPN siRNA group, sham (un-transfected) treated group, and control siRNA group. RNAi effect was investigated by real time PCR, western blotting analysis and ELISA. Then all groups were stimulated with Ang II. The inflammatory activation was assessed by determining the activation of NFκB and activator protein-1 (AP-1), and the release of interleukin-6 (IL-6) and IL-1β. Results:  OPN was knocked down effectively in OPN RNAi group. Inflammatory activations, such as NFκB and AP-1 activation and IL-6 accumulation, were induced by Ang II in sham treated group and control siRNA group. However, it was abolished in OPN siRNA group by the downregulation of OPN compared to sham treated group and control siRNA group. Conclusions:  This result suggested that OPN plays an important role in Ang II-induced inflammatory activation in VSMCs. The finding further supports OPN as a potential target for atherosclerotic therapy. [ABSTRACT FROM AUTHOR]

We have studied the enhancement of radiative emission rate of CdSe/ZnS core-shell quantum dots on semi-continuous gold films which have been prepared by using sputtering technique. The photoluminescence intensity and the decay rate of CdSe/ZnS quantum dots are affected by the semi-continuous gold films. Both the photoluminescence intensity and the decay rate of the quantum dots are greatly enhanced by the semi-continuous gold films near the conductive percolation threshold and that are caused by the enhanced local electric field due to the surface plasmon resonance on the semi-continuous gold films. [ABSTRACT FROM AUTHOR]

To differentiate pigs infected with porcine parvovirus (PPV) from those vaccinated with inactivated whole-virus vaccine, an enzyme-linked immunosorbent assay (ELISA) based on detection of a nonstructural polyprotein 1 (NS1) was developed. A threshold of 0.23 optical density units was established and the assayhad high specificity (100), sensitivity (88), accuracy (90) and positive predictive value (100) using haemagglutination inhibition as the standard method. A reproducibility test revealed that the coefficients of variation of sera within-plates and between-run were less than 10%. The assayshowed no cross-reactivitywith antibodies to porcine reproductive respiratorysyndrome virus, pseudorabies virus, foot and mouth disease virus, Actinobacillus pleuropneumoniae, Toxoplasma or Chlamydia. Sera obtained from pigs infected with PPV reacted with recombinant NS1 protein in the ELISA. Sera from pigs vaccinated with inactivated whole virus did not recognize this protein in the ELISA. In contrast, antibodies against PPV whole virus were present in both PPV-infected and vaccinated animals. Serum conversion against NS1 was first detected 10 days after infection and NS1-specific antibodies were detectable up to half a year post infection. In conclusion, the PPV-NS1 ELISA can differentiate PPV-infected versus inactivated PPV-vaccinated pigs and could be applied in disease diagnosis and surveillance. [ABSTRACT FROM AUTHOR]

Studies were conducted to characterize a HeLa cell model by which the roles of the 85-kDa phospholipase A2 (cPLA2) in interleukin-1 β (IL-1 β) and interleukin-6 (IL-6) release could be evaluated. At first, untreated HeLa cells were compared with lipopolysaccharide (LPS)-treated HeLa cells. The latter resulted in cPLA2 overexpression and an increased trend of IL-1 β and IL-6 release. The indicated doses of 85-kDa cPLA2 antisense oligonucleotide directed against the initiation site were then used to block cPLA2 in LPS-induced HeLa cells. The process led to a dose-dependent decrease in cPLA2 protein with no noticeable change of cPLA2 mRNA. Compared with that of LPS added only, a reduction of IL-1 β and IL-6 levels in the supernatants of transfected cells following the repression of cPLA2 was observed. These results suggested that 85-kDa cPLA2 may mediate the signalling cascades by which IL-1 β and IL-6 were released in LPS-induced HeLa cells. Copyright © 2003 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

An in-situ large-scale underground blast test program was conducted to investigate stress wave characteristics inside the medium, at the soil-rock interface and on the soil ground surface. The stress wave measurements were made through a vertical borehole and a horizontal borehole inside the rock mass, and along several horizontal lines arranged at the rock-soil interface and on the soil surface. Three different charge weights of 0.5, 2.5 and 10 t with loading densities of 0.5, 2.5 and 10 kg/m 3, respectively, were used in the detonation. The measured stress wave time histories and their characteristic parameters, such as peak particle velocity (PPV) and peak particle acceleration (PPA), as well as the principal frequency (PF) at different locations are presented and analyzed in this paper. The results are also compared with those recorded from small-scale tests in a previous study and those from some other researchers, and the pertinent scale effects are discussed by observing differences of the stress wave intensities between the small-scale and the large-scale tests. [ABSTRACT FROM AUTHOR]

We theoretically investigate the quantum Hall effect in a graphene superlattice (GS) system, in which the two valleys of graphene are coupled together. In the presence of a perpendicular magnetic field, an ordinary quantum Hall effect is found with the sequence . At the zeroth Hall platform, a valley-chiral Hall state stemming from the single K or valley is found and it is localized only on one sample boundary contributing to the longitudinal conductance but not to the Hall conductivity. Our findings may shed light on the graphene-based valleytronics applications. [ABSTRACT FROM AUTHOR]

Recently neural crest derived multipotent progenitors from skin have attracted much attention as the skin may provide an accessible, autologous source of stem cells available with therapeutic potential (Toma JG et al.2001 Nat. Cell Biol. 3, 778–784). The multipotent property of stem cells could be tracked back to the expression of specific marker genes that are exclusively expressed in multipotent stem cells rather than any other types of differentiated cells. Here we demonstrate the property of multipotency and neural crest origin of porcine GFP-transgenic skin derived progenitors (termed pSKP) in vitro by marker gene expression analysis. The pSKP cells were isolated from the back skin of GFP transgenic fetuses by serum-free selection culture in the presence of EGF (20 ng mL-1) and bFGF (40 ng mL-1), and developed into spheres in 1–2 weeks (Dyce PW et al.2004 Biochem. Biophy. Res. Commun. 316, 651–658). Three groups of RT-PCR primers were used on total RNA from purified pSKP cells: pluripotency related genes (Oct4, Sox2, Nanog, Stat3), neural crest marker genes (p75NGFR, Slug, Twist, Pax3, Sox9, Sox10) and lineage specific genes (GFAP, tubulin β-III, leptin). Expression of both pluripotency related genes and neural crest marker genes were detected in undifferentiated pSKP cells. In addition, transcripts for fibronectin, vimentin and nestin (neural stem cell marker) were also present. The percentage of positive cells for Oct4, fibronection and vimentin were 12.3%, 67.9% and 53.7% respectively. Differentiation assays showed the appearance of tubulin β-III positive (39.4%) and GFAP-positive (42.6%) cells in cultures by immunocytochemistry, which share the characteristics of neurons and glial cells, respectively. Thus, we confirm the multiple lineage potentials and neural crest origin of pSKP cells in the level of marker gene expression.This work was funded by National Institutes of Health National Center for Research Resources RR013438. [ABSTRACT FROM AUTHOR]

We report that the intraspecific structural colouration variation of the beetle Torynorrhina flammea is a result of diffraction shifting manipulated by a multilayer sub-structure contained in a three-dimensional (3D) photonic architecture. With a perpendicularly 2D quasiperiodic diffraction grating inserted into the multilayer, the 3D photonic structure gives rise to anticrossing bandgaps of diffraction from the coupling of grating and multilayer bands. The angular dispersion of diffraction induced by the multilayer band shift behaves normally, in contrast to the ‘ultranegative’ behaviour controlled by the quasiperiodic grating. In addition, the diffraction wavelength is more sensitive to the multilayer periodicity than the diffraction grating constant, which explains the ‘smart’ biological selection of T. flammea in its intraspecific colouration variation from red to green to blue. The elucidated mechanism could be advantageous for the potential exploration of novel dispersive optical elements. [ABSTRACT FROM AUTHOR]

A foreword to "International Journal of Structural Stability & Dynamics" is presented.

Somatic cell nuclear transfer (SCNT) is a promising technology with potential applications in both agriculture and regenerative medicine. The reprogramming of differentiated somatic nuclei into totipotent embryonic state following NT is not efficient and the mechanism is currently unknown. However, accumulating evidence suggests that faulty epigenetic reprogramming is likely to be the major cause of low success rates observed in all mammals produced through SCNT. It has been demonstrated that increased histone acetylation in reconstructed embryos by applying histone deacetylases inhibitor (HDACi) such as trychostatin A (TSA) significantly enhanced the developmental competence in several species in vitroand in vivo. However TSA has been known to be teratogenic. Compared with TSA, Scriptaid is a low toxic but more efficient HDACi (Su GH et al.2000 Cancer Res. 60, 3137–3142). The objectives of this study were: 1) to investigate and optimize the application Scriptaid to the NT using Landrace fetal fibroblast cells (FFCs) as donor; 2) investigate the effect of increased histone acetylation on the developmental competence of reconstructed embryos from NIH mini inbred FFCs in vitroand in vivo. The reconstructed embryos were treated with Scriptaid at different concentrations (0 nm, 250 nm, 500 nmand 1000 nm) after activation for 14 to 16 h. IVF embryos without treatment were produced as an additional control. Developmental rates to the 2-cell and blastocyst stage were determined. Developmental potential was determined by transferring Day 1 NT zygotes to the oviducts of surrogates on the day of, or one day after, the onset of estrus. Experiments were repeated at least 3 times and data were analyzed with chi-square tests using SAS 6.12 program (SAS institute, Inc., Cary, NC, USA). The percentage blastocyst of cloned embryos using Landrace FFCs as donors treated with 500 nmScriptaid was the highest and was significantly higher than untreated group (25% v. 11%, P< 0.05). Percent cleaved was not different among four treatment groups. We used 500 nmScriptaid for 14 to 16 h after activation for all subsequent experiments. Developmental rate to the blastocyst stage was significantly increased in cloned embryos derived from NIH mini inbred FFCs after treating with Scriptaid (21% v. 9%, P< 0.05), while the blastocyst rate in IVF group was 30%. Embryo transfer (ET) results showed that 5/6 (Transferred embryos No. were 190, 109, 154, 174, 152, and 190, respectively) surrogates (83%) became pregnant resulting in 2 healthy piglets from 2 litters (recipients received 190 and 154 embryos, respectively) in the Scriptaid treatment group, while no pregnancies were obtained in the untreated group from 5 ET (Embryos transferred No. are 140, 163, 161, 151 and 151, respectively). These results suggest that 500 nmScriptaid treatment following activation increase both the in vitroand in vivodevelopment of porcine SCNT embryos from NIH mini inbred FFCs and the hyperacetylation might actually improve reprogramming of the somatic nuclei after NT.Funding from the National Institutes of Health National Center for Research Resources RR018877. [ABSTRACT FROM AUTHOR]

Somatic cell nuclear transfer (SCNT) in pigs relies primarily on the utilization of fetal-derived fibroblast cells, and the resultant clones tend to exhibit a significant level of phenotypic instability, which may be due to epigenetic reprogramming and/or genomic damage in the donor cells. In addition to the compromised phenotypic stability, production of transgenic clones through SCNT is inefficient, because the restricted lifespan of somatic donor cells in culture can be limiting when the genetic modification requires selection. In contrast, stem cells proliferate rapidly and do not undergo senescence at a high rate, so the selection process can be extended. Since there is no report of an embryonic stem cell line derived in the pig that could contribute to the germ line, we decided to investigate the utility of porcine skin-derived stem cells (SSCs). Porcine SSCs were isolated from the skin on the back of day 35 to 50 Yorkshire fetuses. The SSCs were cultured continually in SSCs medium (DMEM/F12 containing B-27, 20 ng mL-1of epidermal growth factor, and 40 ng mL-1of basic fibroblast growth factor) at 37.8°C, 5% CO2, 95% air. The SSCs expressed the neural progenitor marker nestin, as well as genes that are critical for pluripotency, such as Oct4 and Stat3. The SSCs proliferated actively in vitroand retained a normal karyotype after long-term culture. Electron microscopy revealed 2 distinct cell types within the spheres; elongated cells at the sphere periphery had invaginated nuclear envelopes and prominent nucleoli, and these cells displayed few, but large elongated mitochondria with transversal cristae as well as large cisternae of rough endoplasmic reticulum. In contrast, the cells in the center of the spheres were predominantly round-shaped, with a large round nucleus or cuboidal. The SSCs can be genetically modified with long-term positive selection, and 50 μg mL-1G418 appeared to be an appropriate dose of G418 for selection of the transfected SSCs. Finally, NT embryos reconstructed with SSCs showed high rates of pre- and post-implantation development.The cell number in the blastocyst stage embryos derived from cloning with the SSC was significantly higher than those of the blastocysts derived from IVF (28.5 ± 1.9, 16.8 ± 4.0, respectively, P< 0.05), although there was no significant difference in blastocyst formation rates between these groups (21 to 25%). Three of the animals became pregnant in 4 surrogate gilts which received cloned embryos and reached to term. Two healthy male cloned piglets and 1 healthy female cloned piglet are genetically identical to the SSCs.Funding for this study was provided by the National Institutes of Health. [ABSTRACT FROM AUTHOR]

Although transgenic animals have been successfully cloned, the process is still inefficient. One of the limitations is the use of somatic donor cells that have a limited lifespan. If a genetic modification is made, the selection process must be initiated and completed rapidly or the cells will undergo senescence. Identification of a stem cell that would proliferate rapidly and not undergo senescence would prove to be very valuable. Here we report attempts at cloning by using porcine skin-derived sphere stem cells to determine if they are a suitable donor cell type. Skin-derived stem cells were isolated from fetal skin and express the neural progenitor marker NES, as well as genes that may be critical for pluripotency such as POU5F1 and STAT3. The skin-derived stem cells proliferate rapidly in vitro and retain a normal karyotype after long-term culture. In the present study, skin-derived stem cells were cultured and frozen in liquid nitrogen from passage 1 to passage 8. To investigate the developmental potential of the skin-derived stem cells, we performed nuclear transfer (NT) and compared their preimplantation developmental efficiency to that of the embryos derived from in vitro fertilization (IVF). Cumulus–oocyte complexes (COCs) were aspirated from antral follicles of ovaries from prepubertal gilts. Approximately, groups of 50-70 COCs were matured in vitro in 500 µL TCM-199 per culture well for 40–44 h at 38.5C, in a humidified atmosphere of 5% CO2 in air. The donor cells were thawed and cultured one day before NT; skin-derived stem cells were pipetted vigorously in PBS-EDTA to isolate individual cells. For IVF, cryopreserved ejaculated spermatozoa were thawed and washed and then resuspended with fertilization medium (mTBM). The MII oocytes were co-incubated with sperm for 6 h, and then transferred to PZM3 and cultured. For NT and IVF, respectively, the percent cleavage at 48 h in PZM3 was 64.9 8.2% (169/208) and 62.1 3.1% (94/184) (P > 0.05), the percent blastocysts after 6 days was 21.5 5.8% (53/208) and 25.2 3.4% (46/184) (P > 0.05), and the number of nuclei per blastocyst was 28.5 1.9 (NT, maximum was 58) and 16.8 4.0 (IVF, maximum was 31) (P < 0.05). To determine development post-implantation, some cloned embryos were cultured in PZM3 for 15.5 h and an average of 112 cloned embryos were transferred to the oviducts of four naturally cycling gilts on Day 0–1 of standing estrus. Three of the animals were pregnant: one of them farrowed two male piglets on August 14th, with the other two due on September 8th and 9th. Future studies will involve performing NT and ET on skin-derived stem cells from a higher passage number to determine if they would be suitable for genetic modification prior to NT. [ABSTRACT FROM AUTHOR]