A Reaction Between High Mn-High Al Steel and CaO-SiO2-Type Molten Mold Flux: Part I. Composition Evolution in Molten Mold Flux

In order to elucidate the reaction mechanism between high Mn-high Al steel such as twin-induced plasticity steel and molten mold flux composed mainly of CaO-SiO2 during continuous casting process, a series of laboratory-scale experiments were carried out in the present study. Molten steel and molten flux were brought to react in a refractory crucible in a temperature range between 1713 K to 1823 K (1440 A degrees C to 1550 A degrees C) and composition evolution in the steel and the flux was analyzed using inductively coupled plasma atomic emission spectroscopy, X-ray fluorescence, and electron probe microanalysis. The amount of SiO2 in the flux was significantly reduced by Al in the steelthus, Al2O3 was accumulated in the flux as a result of a chemical reaction, 4[Al] + 3(SiO2) = 3[Si] + 2(Al2O3). In order to find a major factor which governs the reaction, a number of factors ((pct CaO/pct SiO2), (pct Al2O3), [pct Al], [pct Si], and temperature) were varied in the experiments. It was found that the above chemical reaction was mostly governed by [pct Al] in the molten steel. Temperature had a mild effect on the reaction. On the other hand, (pct CaO/pct SiO2), (pct Al2O3), and [pct Si] did not show any noticeable effect on the reaction. Apart from the above reaction, the following reactions are also thought to happen simultaneously: 2[Mn] + (SiO2) = [Si] + 2(MnO) and 2[Fe] + (SiO2) = [Si] + 2(FeO). These oxide components were subsequently reduced by Al in the molten steel. Na2O in the molten flux was gradually decreased and the decrease was accelerated by increasing [pct Al] and temperature. Possible reactions affecting the Al2O3 accumulation are summarized.ope

Factors influencing school connectedness: Chinese adolescents' perspectives

This study explored the concept of school connectedness and the factors that may influence its development with a sample of Chinese adolescents. Six focus groups involving 52 high school students were conducted using a set of predetermined discussion topics. Results indicated that the students fully understood the notion of school connectedness and could identify a number of key influences affecting its development. These factors could be grouped under several domains including teacher care, peer relations, broader school relationships, school disciplinary policies and practices, activities within the school's guidance and counseling program, and opportunities for talent development. The students were also able to suggest practical strategies that schools might introduce to enhance and strengthen students' acquisition of connectedness to school. The implications from the findings are discussed with particular reference to implementing comprehensive school guidance and counseling program in Hong Kong. © 2011 The Author(s).published_or_final_versionSpringer Open Choice, 21 Feb 201

UV Photofunctionalization Effect on Bone Graft in Critical One-Wall Defect around Implant: A Pilot Study in Beagle Dogs

published_or_final_versio

Enhancing life skills development: Chinese adolescents' perceptions

This study explored Chinese adolescents' perceptions of their own life skills development and the importance they place on such skills. The study also investigated the within-school and outsideschool influences that may help develop and enhance life skills development. Six focus groups involving 52 high school students were conducted, using a set of predetermined discussion topics. Results revealed students' awareness of many salient life skills, including those related directly to academic development, 'learning to learn', personal and social growth, and future career planning. The students were also able to suggest practical strategies that schools might use to further enhance students' life skills development. Contextual factors influencing the development of life skills appear to include not only experiences within the school curriculum and the guidance and counseling program, but also talent development opportunities, and family and peer relationships. The implications of the findings are discussed with particular reference to implementing comprehensive school guidance and counseling programs in Hong Kong. © 2010 NAPCE.postprin

Cell abundance aware deep learning for cell detection on highly imbalanced pathological data

Automated analysis of tissue sections allows a better understanding of disease biology, and may reveal biomarkers that could guide prognosis or treatment selection. In digital pathology, less abundant cell types can be of biological significance, but their scarcity can result in biased and sub-optimal cell detection model. To minimize the effect of cell imbalance on cell detection, we proposed a deep learning pipeline that considers the abundance of cell types during model training. Cell weight images were generated, which assign larger weights to less abundant cells and used the weights to regularize Dice overlap loss function. The model was trained and evaluated on myeloma bone marrow trephine samples. Our model obtained cell detection F1-score of 0.78, a 2% increase compared to baseline models, and it outperformed baseline models at detecting rare cell types. We found that scaling deep learning loss function by the abundance of cells improves cell detection performance. Our results demonstrate the importance of incorporating domain knowledge on deep learning methods for pathological data with class imbalance

Algebraic charge liquids

High temperature superconductivity emerges in the cuprate compounds upon changing the electron density of an insulator in which the electron spins are antiferromagnetically ordered. A key characteristic of the superconductor is that electrons can be extracted from them at zero energy only if their momenta take one of four specific values (the `nodal points'). A central enigma has been the evolution of the zero energy electrons in the metallic state between the antiferromagnet and the superconductor, and recent experiments yield apparently contradictory results. The oscillation of the resistance in this metal as a function of magnetic field indicate that the zero energy electrons carry momenta which lie on elliptical `Fermi pockets', while ejection of electrons by high intensity light indicates that the zero energy electrons have momenta only along arc-like regions. We present a theory of new states of matter, which we call `algebraic charge liquids', which arise naturally between the antiferromagnet and the superconductor, and reconcile these observations. Our theory also explains a puzzling dependence of the density of superconducting electrons on the total electron density, and makes a number of unique predictions for future experiments.Comment: 6+8 pages, 2 figures; (v2) Rewritten for broader accessibility; (v3) corrected numerical error in Eq. (5

Vaccinia-related kinase 1 promotes hepatocellular carcinoma by controlling the levels of cell cycle regulators associated with G1/S transition

We identified the specific role of vaccinia-related kinase 1 (VRK1) in the progression of hepatocellular carcinoma (HCC) and evaluated its therapeutic and prognostic potential. VRK1 levels were significantly higher in HCC cell lines than a normal hepatic cell line, and were higher in HCC than non-tumor tissue. VRK1 knockdown inhibited the proliferation of SK-Hep1, SH-J1 and Hep3B cells; moreover, depletion of VRK1 suppressed HCC tumor growth in vivo. We also showed that VRK1 knockdown increased the number of G1 arrested cells by decreasing cyclin D1 and p-Rb while upregulating p21 and p27, and that VRK1 depletion downregulated phosphorylation of CREB, a transcription factor regulating CCND1. Additionally, we found that luteolin, a VRK1 inhibitor, suppressed HCC growth in vitro and in vivo, and that the aberrant VRK1 expression correlated with poor prognostic features of HCC. High levels of VRK1 were associated with shorter overall and disease-free survival and higher recurrence rates. Taken together, our findings suggest VRK1 may act as a tumor promoter by controlling the level of cell cycle regulators associated with G1/S transition and could potentially serve as a therapeutic target and/or prognostic biomarker for HCC.1110Ysciescopu

Dopamine Regulation of Amygdala Inhibitory Circuits for Expression of Learned Fear.

GABAergic signaling in the amygdala controls learned fear, and its dysfunction potentially contributes to posttraumatic stress disorder (PTSD). We find that sub-threshold fear conditioning leads to dopamine receptor D4-dependent long-term depression (LTD) of glutamatergic excitatory synapses by increasing inhibitory inputs onto neurons of the dorsal intercalated cell mass (ITC) in the amygdala. Pharmacological, genetic, and optogenetic manipulations of the amygdala regions centered on the dorsal ITC reveal that this LTD limits less salient experiences from forming persistent memories. In further support of the idea that LTD has preventive and discriminative roles, we find that LTD at the dorsal ITC is impaired in mice exhibiting PTSD-like behaviors. These findings reveal a novel role of inhibitory circuits in the amygdala, which serves to dampen and restrict the level of fear expression. This mechanism is interfered with by stimuli that give rise to PTSD and may also be recruited for fear-related psychiatric diseases.1110Ysciescopu

Microwave Oscillations of a Nanomagnet Driven by a Spin-Polarized Current

We describe direct electrical measurements of microwave-frequency dynamics in individual nanomagnets that are driven by spin transfer from a DC spin-polarized current. We map out the dynamical stability diagram as a function of current and magnetic field, and we show that spin transfer can produce several different types of magnetic excitations, including small-angle precession, a more complicated large-angle motion, and a high-current state that generates little microwave signal. The large-angle mode can produce a significant emission of microwave energy, as large as 40 times the Johnson-noise background.Comment: 12 pages, 3 figure