Analysis of Slab and Slab Heater Cover in a Compact Endless Cast and Rolling Mill Process using Finite Element Methods

Compact Endless cast and rolling Mill (CEM) processes were developed and used to fabricate steel products such as steel slabs. However, the coiling furnace in this process was very expensive, so a new layout was suggested. As the coiling furnace was removed, the interval among the slab heaters had to be increased. This led to a temperature drop in the slab. The temperature distribution of the slab impacts quality, so new layout was developed. This paper presents a Finite Element Method (FEM) simulation of thermal behavior in the slab employing slab heater covers. All of the simulation results were verified by comparing them with experimental results. The slab moving distance at which the temperature was saturated during the process was determined to consider the steady-state and analyze the temperature distribution of the slab and slab heater. Those results revealed that the efficiency of heat conservation increased by more than 50% using the slab heater cover. Finally, a sensitivity analysis of the slab heater cover was conducted with respect to the cover design. The effects of insulator thickness, the gap distance between the slab and cover, and material parameters such as density, and specific heat were investigated to optimize the design of the slab heater cover to produce the best quality slab.11Ysciescopuskc

PIERCE1 is critical for specification of left-right asymmetry in mice.

The specification of left-right asymmetry of the visceral organs is precisely regulated. The earliest breakage of left-right symmetry occurs as the result of leftward flow generated by asymmetric beating of nodal cilia, which eventually induces asymmetric Nodal/Lefty/Pitx2 expression on the left side of the lateral plate mesoderm. PIERCE1 has been identified as a p53 target gene involved in the DNA damage response. In this study, we found that Pierce1-null mice exhibit severe laterality defects, including situs inversus totalis and heterotaxy with randomized situs and left and right isomerisms. The spectrum of laterality defects was closely correlated with randomized expression of Nodal and its downstream genes, Lefty1/2 and Pitx2. The phenotype of Pierce1-null mice most closely resembled that of mutant mice with impaired ciliogenesis and/or ciliary motility of the node. We also found the loss of asymmetric expression of Cerl2, the earliest flow-responding gene in the node of Pierce1-null embryos. The results suggest that Pierce1-null embryos have defects in generating a symmetry breaking signal including leftward nodal flow. This is the first report implicating a role for PIERCE1 in the symmetry-breaking step of left-right asymmetry specification.1110Ysciescopu

Brazilin Isolated from Caesalpinia sappan Suppresses Nuclear Envelope Reassembly by Inhibiting Barrier-to-Autointegration Factor Phosphorylation

To date, many anticancer drugs have been developed by directly or indirectly targeting microtubules, which are involved in cell division. Although this approach has yielded many anticancer drugs, these drugs produce undesirable side effects. An alternative strategy is needed, and targeting mitotic exit may be one alternative approach. Localization of phosphorylated barrier-to-autointegration factor (BAF) to the chromosomal core region is essential for nuclear envelope compartment relocalization. In this study, we isolated brazilin from Caesalpinia sappan Leguminosae and demonstrated that it inhibited BAF phosphorylation in vitro and in vivo. Moreover, we demonstrated direct binding between brazilin and BAF. The inhibition of BAF phosphorylation induced abnormal nuclear envelope reassembly and cell death, indicating that perturbation of nuclear envelope reassembly could be a novel approach to anticancer therapy. We propose that brazilin isolated from C. sappan may be a new anticancer drug candidate that induces cell death by inhibiting vaccinia-related kinase 1-mediated BAF phosphorylation.X1153Ysciescopu

Wnt5a stimulates chemotactic migration and chemokine production in human neutrophils

Wnt5a is a ligand that activates the noncanonical Wnt signaling pathways (??-catenin-independent pathways). Human neutrophils expressed several Wnt5a receptors, such as Frizzled 2, 5 and 8. Stimulation of human neutrophils with Wnt5a caused chemotactic migration and the production of two important chemokines, CXCL8 and CCL2. CCL2 production by Wnt5a was mediated by a pertussis toxin-sensitive G-protein-dependent pathway. Wnt5a also stimulated the phosphorylation of three mitogen-activated protein kinases (MAPKs: ERK, p38 MAPK and JNK) and Akt. Inhibition of ERK, p38 MAPK or JNK by specific inhibitors induced a dramatic reduction in Wnt5a-induced CCL2 production. Supernatant collected from lipopolysaccharide-stimulated macrophages induced neutrophil chemotaxis, which was significantly inhibited by anti-Wnt5a antibody. Our results suggested that Wnt5a may contribute to neutrophil recruitment, mediating the inflammation response.open4

RNA editing signature during myeloid leukemia cell differentiation

Adenosine deaminases acting on RNA (ADARs) are key proteins for hematopoietic stem cell self-renewal and for survival of differentiating progenitor cells. However, their specific role in myeloid cell maturation has been poorly investigated. Here we show that ADAR1 is present at basal level in the primary myeloid leukemia cells obtained from patients at diagnosis as well as in myeloid U-937 and THP1 cell lines and its expression correlates with the editing levels. Upon phorbol-myristate acetate or Vitamin D3/granulocyte macrophage colony-stimulating factor (GM-CSF)-driven differentiation, both ADAR1 and ADAR2 enzymes are upregulated, with a concomitant global increase of A-to-I RNA editing. ADAR1 silencing caused an editing decrease at specific ADAR1 target genes, without, however, interfering with cell differentiation or with ADAR2 activity. Remarkably, ADAR2 is absent in the undifferentiated cell stage, due to its elimination through the ubiquitin–proteasome pathway, being strongly upregulated at the end of the differentiation process. Of note, peripheral blood monocytes display editing events at the selected targets similar to those found in differentiated cell lines. Taken together, the data indicate that ADAR enzymes play important and distinct roles in myeloid cells

MicroRNA-34a modulates genes involved in cellular motility and oxidative phosphorylation in neural precursors derived from human umbilical cord mesenchymal stem cells

<p>Abstract</p> <p>Background</p> <p>Mesenchymal stem cell (MSC) found in bone marrow (BM-MSCs) and the Wharton's jelly matrix of human umbilical cord (WJ-MSCs) are able to transdifferentiate into neuronal lineage cells both <it>in vitro </it>and <it>in vivo </it>and therefore hold the potential to treat neural disorders such as stroke or Parkinson's disease. In bone marrow MSCs, miR-130a and miR-206 have been show to regulate the synthesis of neurotransmitter substance P in human mesenchymal stem cell-derived neuronal cells. However, how neuronal differentiation is controlled in WJ-MSC remains unclear.</p> <p>Methods</p> <p>WJ-MSCs were isolated from human umbilical cords. We subjected WJ-MSCs into neurogenesis by a published protocol, and the miRNome patterns of WJ-MSCs and their neuronal progenitors (day 9 after differentiation) were analyzed by the Agilent microRNA microarray.</p> <p>Results</p> <p>Five miRNAs were enriched in WJ-MSCs, including miR-345, miR-106a, miR-17-5p, miR-20a and miR-20b. Another 11 miRNAs (miR-206, miR-34a, miR-374, miR-424, miR-100, miR-101, miR-323, miR-368, miR-137, miR-138 and miR-377) were abundantly expressed in transdifferentiated neuronal progenitors. Among these miRNAs, miR-34a and miR-206 were the only 2 miRNAs been linked to BM-MSC neurogenesis. Overexpressing miR-34a in cells suppressed the expression of 136 neuronal progenitor genes, which all possess putative miR-34a binding sites. Gene enrichment analysis according to the Gene Ontology database showed that those 136 genes were associated with cell motility, energy production (including those with oxidative phosphorylation, electron transport and ATP synthesis) and actin cytoskeleton organization, indicating that miR-34a plays a critical role in precursor cell migration. Knocking down endogenous miR-34a expression in WJ-MSCs resulted in the augment of WJ-MSC motility.</p> <p>Conclusions</p> <p>Our data suggest a critical role of miRNAs in MSC neuronal differentiation, and miR-34a contributes in neuronal precursor motility, which may be crucial for stem cells to home to the target sites they should be.</p

Revealing the nature of morphological changes in carbon nanotube-polymer saturable absorber under high-power laser irradiation

Composites of single-walled carbon nanotubes (SWNTs) and water-soluble polymers (WSP) are the focus of significant worldwide research due to a number of applications in biotechnology and photonics, particularly for ultrashort pulse generation. Despite the unique possibility of constructing non-linear optical SWNT-WSP composites with controlled optical properties, their thermal degradation threshold and limit of operational power remain unexplored. In this study, we discover the nature of the SWNT-polyvinyl alcohol (PVA) film thermal degradation and evaluate the modification of the composite properties under continuous high-power ultrashort pulse laser operation. Using high-precision optical microscopy and micro-Raman spectroscopy, we have examined SWNT-PVA films before and after continuous laser radiation exposure (up to 40 hours) with a maximum optical fluence of 2.3 mJ·cm−2. We demonstrate that high-intensity laser radiation results in measurable changes in the composition and morphology of the SWNT-PVA film due to efficient heat transfer from SWNTs to the polymer matrix. The saturable absorber modification does not affect the laser operational performance. We anticipate our work to be a starting point for more sophisticated research aimed at the enhancement of SWNT-PVA films fabrication for their operation as reliable saturable absorbers in high-power ultrafast lasers

Clinical Significance of Thrombosis in an Intracardiac Blind Pouch After a Fontan Operation

The univentricular heart after the Fontan operation may have a blind pouch formed by the pulmonary stump or rudimentary ventricle according to the anatomy before surgery. Thrombosis in an intracardiac blind pouch of patients with a univentricular heart is a hazardous complication. Because only a few reports have described this complication, the authors evaluated the clinical significance of thrombosis in an intracardiac blind pouch of a univentricular heart. They performed a retrospective review of medical records from August 1986 to December 2007. Four patients were confirmed as having thrombosis in a pulmonary artery stump and one patient as having thrombosis in a rudimentary ventricle shown by cardiac computed tomography (CT). This represents 1.85% (5/271) of patients with ongoing regular follow-up evaluation after the Fontan operation. The median age at diagnosis was 14.2 years. Two of the five patients were taking aspirin and one patient was taking warfarin when they were identified for the development of thrombosis. None of the patients demonstrated thrombosis in the Fontan tract or venous side of the circulation. Brain magnetic resonance imaging (MRI) showed that three patients had cerebral infarction and one patient had suggestive old ischemia. Three patients with thrombus in the pulmonary stump underwent pulmonary artery stump thrombectomy and pulmonary valve obliteration. One patient with thrombus in the rudimentary ventricle underwent ventricular septal defect (VSD) closure with thrombectomy. Thrombus in a blind pouch could cause systemic thromboembolism despite little blood communication. Therefore, surgical modification of the pulmonary stump and VSD closure of the rudimentary ventricle are required to reduce the risk of later thrombus formation. Clinicians should not overlook the possibility of thrombus in a ligated pulmonary artery stump or a rudimentary ventricle after the Fontan operation, which may increase the risk of embolic stroke for patients with single-ventricle physiology

Risk factors for bone mineral density at the calcaneus in 40–59 year-old male workers: A cross-sectional study in Korea

<p>Abstract</p> <p>Background</p> <p>Few epidemiologic studies have attempted to investigate the prevalence and risk factors for osteopenia and osteoporosis in middle-aged Asian men. We performed this study to determine the prevalence and risk factors of osteopenia and osteoporosis in this population.</p> <p>Methods</p> <p>This cross-sectional study was conducted from March to July, 2004. The subjects were 2,073 males aged from 40 to 59 years in the KHNP (Korea Hydro & Nuclear Power) workplace-based cohort. Bone mineral density (BMD) was measured by peripheral, dual-energy, X-ray absorptiometry (DXA) at the calcaneus. Anthropometric and lifestyle factors were investigated using a standard, self-reported questionnaire.</p> <p>Results</p> <p>BMD was 0.60 ± 0.09 g/cm²(mean ± standard deviation) and was negatively correlated with age (r = -0.18, <it>P </it>< 0.001), but positively correlated with waist-to-hip ratio (WHR; r = 0.15, <it>P </it>< 0.001), body fat (r = 0.10, <it>P </it>< 0.001), BMI (r = 0.35, <it>P </it>< 0.001), height (r = 0.26, <it>P </it>< 0.001), and weight (r = 0.43, <it>P </it>< 0.001).</p> <p>In multiple linear regression analysis, the independent determinants associated with BMD were increasing age (coefficient = -0.002, <it>P </it>< 0.001), physical activity (≤ 2/week vs. ≥ 3/week; coefficient = 0.017, <it>P </it>< 0.001), WHR (coefficient = -0.796, <it>P </it>< 0.001), body mass index (BMI; coefficient = 0.023, <it>P </it>< 0.001) and smoking status (never vs. ever; coefficient = -0.018, <it>P </it>< 0.001).</p> <p>Conclusion</p> <p>We suggest that BMD of the calcaneus is correlated negatively with exposure to smoke and increased WHR, but positively with regular exercise and increased BMI.</p