A Nonconservative Flow Field for Robust Variational Image Segmentation

We introduce a robust image segmentation method based on a variational formulation using edge flow vectors. We demonstrate the nonconservative nature of this flow field, a feature that helps in a better segmentation of objects with concavities. A multiscale version of this method is developed and is shown to improve the localization of the object boundaries. We compare and contrast the proposed method with well known state-of-the-art methods. Detailed experimental results are provided on both synthetic and natural images that demonstrate that the proposed approach is quite competitive.      

Synthesis,characterization, and property studies of (La,Ag) FeO3 (0.0 ≤ x ≤ 0.3) perovskites

Applying a solution – based combustion process, Ag-doped LaFeO₃ orthoferrites were synthesized. The samples were characterized by multiple techniques to establish structure – property relationships. Specifically, for structural characterization, powder X-ray diffraction (XRD), scanning electron microscopy (SEM), energy dispersive X-ray analysis (EDX), Fourier transmission infrared spectroscopy (FTIR), Thermo-gravimetric analysis (TGA), and X-ray photoelectron microscopy (XPS) were carried out. For properties, squid magnetometer measurements (for magnetic properties), titrations (for chemical analysis), and diffuse reflectance (for optical band gap properties) measurements were carried out to elucidate structure–property relationship.     

Regulation of in vitro and in vivo T cell activation by CD43

Accessory molecule interactions can be critical in determining the outcome of a T cell's encounter with antigen. Cell adhesion proteins may augment T cell responses by facilitating TCR engagement of the antigen-MHC complex, while co-stimulatory molecules may deliver distinct signals that modulate T cell responsiveness. CD43 (leukosialin, sialophorin) has been suggested to influence cell activation by steric hindrance based upon the large size and glycosylation of the protein, as well as the relative abundance of the protein on the cell surface. In this paper we examine both in vitro and in vivo T cell-dependent responses in CD43-deficient mice. We demonstrate that T cells from CD43-deficient mice are hyper-responsive following both in vivo and in vitro activation, and that this is observed in response to not only TCR-CD3-mediated stimulation, but also following receptor-independent activation. This data suggests that mechanisms other than non-specific steric hindrance are important in the regulation of T cell activation by CD43.     

Solution-combustion synthesis of Bi1−x Ln x O1.5 (Ln = Y and La-Yb) oxide ion conductors

Cubic fluorite related Bi_1−x LnxO1.5 (Ln = Y and LaYb) phases are synthesized by solution-combustion method using glycine as the fuel. The cubic fluorite phase is stabilized with 25 mole% of rare earth cations. The lattice parameter of cubic phase increases linearly with size of the lanthanide ion. The synthesized powders are nano-metric in size and exhibit excellent compactability and reach 98% densification even on short period of sintering. The oxides with relatively larger cations Nd, Sm, Eu, Pr and Gd with 25 mole% composition transform to rhombohedral structure while others retain cubic upon sintering. All the phases show high oxide-ion conductivity and the values obtained are in good agreement with the reported values.     

Molecular cloning of a zinc finger gene eZNF from a human inner ear cDNA library, and in situ expression pattern of its mouse homologue in mouse inner ear

A mathematical model of posttetanic processes launched by rhythmic stimulation of the excitatory and inhibitory inputs to the dendritic spine of a pyramidal neuron in hippocampal field CA3 was used to study conditions for modifying the efficiency of the inhibitory input. The level of dephosphorylation of GABAa and GABAb receptors, which determines the GABA sensitivity of these receptors, was shown to depend on the Ca(2+)-dependent ratio of active protein kinases and protein phosphatases; the level of dephosphorylation decreased monotonically as the intracellular Ca2+ increased. Posttetanic increases and decreases in the Ca2+ concentration, as compared with the level achieved during the previous stimulation, led to increases or decreases respectively in the number of dephosphorylated GABA receptors and to induction of long-term potentiation and depression, respectively, in the efficiency of inhibitory transmission. The extent of the modification effect depended on the ratio of the quantities of inhibitory and excitatory mediators in the synaptic cleft. At very low or very high GABA concentrations, modification of inhibitory transmission was insignificant.     

TCR signaling induces selective exclusion of CD43 from the T cell-antigen-presenting cell contact site

CD43, a large highly glycosylated molecule, is arguably the most abundant molecule on the surface of T cells. Nevertheless, the function of CD43 remains unclear. Utilizing fluorescence microscopy, we find that CD43 is excluded from the T cell-APC contact site. This exclusion is Ag dependent since optimal CD43 exclusion requires Ag-pulsed APC, and since signaling through CD3, in the absence of any other receptor ligand interactions, can induce the modulation of CD43. These data suggest that CD43 may function as a barrier to nonspecific T cell-APC interactions that is removed as a result of T cell activation. Exclusion from the interaction site is a unique feature of CD43 and not universally found for all large highly glycosylated molecules since CD45 is not excluded. Thus, CD43 may represent a novel regulatory molecule on the T cell surface that can direct T cell interactions by changing its location on the cell surface.     

Entropy Generation and Thermo‐Economic Analysis of Constructal Heat Exchanger

Comparison of a constructal heat exchanger (CHE) and normal heat exchanger (NHE) is analyzed by using second law analysis. Analysis is carried out by considering the three irreversibilities due to heat transfer, pressure drop, and production of the materials and the construction of the heat exchanger. The entropy generation minimization method is used to formulate the entropy generation number expressions of all three irreversibilities for both CHE and NHE to study the differences. Also to realize the advantages of the CHE over the NHE, ratios of each of the entropy generation numbers are considered. Additionally, the thermo‐economic aspect of the heat exchanger is considered to further analyze the economic differences between the CHE and NHE. Graphical results are presented to investigate the influence of different parameters such as the number of pairing levels and initial length‐to‐diameter ratio on the behavior of the three entropy generation numbers along with effectiveness and NTU. From the overall results, we can find that there is an increase in the performance and a cost reduction in the CHE when compared to the NHE. © 2013 Wiley Periodicals, Inc. Heat Trans Asian Res, 43(1): 39–60, 2014; Published online in Wiley Online Library ( wileyonlinelibrary.com/journal/htj ). DOI 10.1002/htj.21062     

Rauvolfia serpentina-Mediated Green Synthesis of CuO Nanoparticles and Its Multidisciplinary Studies

Copper oxide nanoparticles(Cu O Nps) were successfully synthesized by solution combustion method using aqueous leaf extract of Rauvolfia serpentina as a fuel. The structure and morphology of the Cu O nanoparticles(Nps) were characterized by powder X-ray diffraction(PXRD), UV–visible spectroscopy(UV–visible), scanning electron microscopy(SEM), transmission electron microscopy(TEM), etc. The PXRD patterns reveal the formation of monoclinic phase with crystallite structure. SEM images indicate that the particles have sponge-like structure being highly porous and agglomerated with large surface area. The average crystallite sizes were found to be in the range of 10–20 nm by Scherrer's method. The Cu O Nps size was further confirmed by TEM. Further, Cu O Nps exhibit good photocatalytic activity for the photodegradation of trypan blue dye, indicating that it acts as a promising semiconducting material. The antibacterial properties of Cu O nanoparticles were investigated against pathogenic bacterial strains, namely Gram-ve Escherichia coli(NCIM-5051) and Pseudomonas desmolyticum(NCIM-2028) and Gram ?ve bacteria Staphylococcus aureus(NCIM-5022) using the agar well diffusion method.     

利用神经网络模型预测球团矿的冷压强度(英文)

建立了一个神经网络模型来预测球团矿的冷压强度,该网络模型采用三层前向BP神经网络,网络结构为12-12-1,12个输入变量分别为给料率、料层高度、焙烧温度、干透点温度、COREX煤气单耗、膨润土的添加量、生球水分、生球碳含量以及成品球的FeO、MgO、Al2O3含量和碱度;隐层含有12个神经元;输出为成品球团冷压强度;神经元激活函数选择双曲正切函数;神经网络学习算法使用的是带惯量项的误差反向传播学习算法(BP学习算法)。选取353组数据来训练和测试神经网络,其中247组数据用于训练网络,其余数据用于测试网络。测试结果表明,该网络的预测结果与实际结果的误差在3%以内,同时通过敏感性分析得出以下结论:①膨润土添加量、生球碳含量以及成品球的FeO、MgO、Al2O3含量和碱度对球团矿的冷压强度有重要影响;②增加膨润土添加量、成品球碱度、MgO含量、焙烧温度、干透点温度、COREX煤气单耗有助于改善球团矿的冷压强度;③增加FeO含量、生球碳含量、Al2O3含量、料层高度、给料率将使球团矿的冷压强度迅速下降;④增加生球水分会降低冷压强度;⑤提高球团矿冷压强度的参数设置(膨润土的添加量:0.86%～0.92%;wFeO<0.5%;生球碳含量:1.00%～1.10%;MgO含量:0.39%～0.44%);⑥在0.3～0.7范围内增加碱度不能显著改善球团矿的冷压强度。