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We show that the photonic crystal (PhC) made of dielectric cuboids with their centers forming a honeycomb lattice is characterized by a ℤ2${\mathbb{ℤ}}_{2}$topological index when the longer sides of six cuboids point towards the center of hexagonal unit cell. While the C6vsymmetry regarding the center of unit cell is preserved, the C3symmetry regarding honeycomb sites is broken, which opens a bandgap in the Dirac dispersion of honeycomb structure and induces a band inversion between pmodes and dmodes. Rotating cuboids around their individual centers closes the bandgap and reopens a trivial bandgap. We discuss that this feature can be exploited for realizing a reconfigurable topological waveguide.

Topological insulators are materials that behave as insulators in the bulk and as conductors at the edge or surface due to the particular configuration of their bulk band dispersion. However, up to date possible practical applications of this band topology on materials’ bulk properties have remained abstract. Here, we propose and experimentally demonstrate a topological bulk laser. We pattern semiconductor nanodisk arrays to form a photonic crystal cavity showing topological band inversion between its interior and cladding area. In-plane light waves are reflected at topological edges forming an effective cavity feedback for lasing. This band-inversion-induced reflection mechanism induces single-mode lasing with directional vertical emission. Our topological bulk laser works at room temperature and reaches the practical requirements in terms of cavity size, threshold, linewidth, side-mode suppression ratio and directionality for most practical applications according to Institute of Electrical and Electronics Engineers and other industry standards. We believe this bulk topological effect will have applications in near-field spectroscopy, solid-state lighting, free-space optical sensing and communication.

Accumulating evidence has demonstrated that endothelial progenitor cells (EPCs) could facilitate the reendothelialization of injured arteries by replacing the dysfunctional endothelial cells, thereby suppressing the formation of neointima. Meanwhile, other findings suggest that EPCs may be involved in the pathogenesis of age-related vascular remodeling. This review is presented to summarize the characteristics of EPCs and age-related vascular remodeling. In addition, the role of EPCs in age-related vascular remodeling and possible solutions for improving the therapeutic effects of EPCs in the treatment of age-related diseases are discussed.

Peanut (Arachis hypogaeaL.) yield and quality are seriously compromised by consecutive monoculturing in southeastern China. This work investigated the population size and community structure of soil nematodes in 3‐, 6‐, and 20‐yr‐old peanut monoculturing systems. A grass pasture was used as the control. The results showed that continuous peanut monocropping had detrimental effects on the soil nematode abundance and functional composition compared with the control. The reductions in the abundance of total and microbivorous nematodes with increasing years of monocropping are likely to reduce bioturbation and nutrient mineralization, and an elevated abundance of plant parasitic nematodes may result in serious damage to peanut roots, thus aggravating root rot. Furthermore, the significant variations in soil nematode functional indices across the three monocropped peanut fields may produce negative effects on sustainable agroecosystems. Our study also contributes to the identification of locally applicable indicator species of soil nematodes, i.e., Tylenchus, Doryllium, and Mesorhabditis, which can be applied in the assessment of soil status within monocropped peanut fields. Our results suggest that the soil nematode community exhibits evident responses to peanut monocropping.

A growing body of evidence in animal models and clinical studies supports the concept that endothelial progenitor cell (EPC)-mediated therapy ameliorates pulmonary arterial hypertension (PAH) and thus may represent a novel approach to treat it. Conversely, several experimental findings suggest that EPCs may be involved in PAH pathogenesis and disease progression. These discrepant results confuse the application of EPC transplantation as an effective treatment strategy for PAH. To improve the study of EPC transplantation in PAH therapy, it is high time that we resolve this dilemma. In this review, we examine the pathobiological changes of PAH, the characteristics of EPCs, and the underlying mechanisms of EPC effects on PAH.

Previous studies have underlined the importance of endothelial dysfunction and microvascular occlusion in the pathogenesis of pulmonary artery hypertension (PAH). Since the endothelial progenitor cells (EPCs) are involved in maintaining endothelial homeostasis, we observed the change of peripheral EPCs in canines before and after PAH onset. PAH was induced by intra-pulmonary artery injection of dehydromonocrotaline (DHMC) in nine beagles. Before and 48 h and 6 weeks after DHMC injection, 40 ml peripheral blood was obtained from the femoral vein. Circulating EPCs were identified as CD133 + KDR + cells and numerated by fluorescence-activated cell sorter; the EPCs functional capacity was determined by in vitro tubule-forming assay. The senescence of EPCs was determined by β-galactosidase staining. At each time point, 2 ml blood from femoral artery was obtained for arterial oxygen pressure (PaO2). Forty-eight  hours after DHMC injection, treated beagles suffered from hypoxemia; however, both the number and the tubule-forming capacity of EPCs were transiently raised. Six weeks later, PAH was confirmed by obviously high mean pulmonary arterial pressure (20.2 ± 1.64 vs. 11.3 ± 2.0 mmHg, p< 0.05) and low PaO2(69.30 ± 9.15 vs. 95.94 ± 1.43 mmHg, p< 0.01) in beagles after DHMC treatment, and their EPCs exhibited a predominant decrease in either the number (206.1 ± 26.8 vs. 632.8 ± 42.8 cells/ml blood, p< 0.01) or the tubule-forming capacity (21.1 ± 2.8 vs. 11.2 ± 2.8 tubules/×200 field, p< 0.01). Additionally, senescence-associated β-galactosidase-positive EPCs were significantly increased. Our data suggested that, after the acute stage of DHMC injury to pulmonary vessels, the EPCs from PAH beagles suffered from exhaustion and senescence.

Magnetic abrasive finishing (MAF) is a kind of method for polishing the surfaces and the edges. The investigation for the technique of MAF and the development of the ferromagnetic poles lay a theoretical foundation for developing a new method for finishing the curved surfaces automatically under the numerical control. In the paper, the performance parameters of the developed magneto poles, which are used for finishing the plane surfaces and the curved ones, have been tested. The curvature of the finished surface, the sloping angle of the machined surface and the rotation speed of the poles, which affect the surface roughness, are studied theoretically. What mentioned above supply references to the practical uses of the MAF, especially in the mould manufacturing.

Hypercholesterolaemia contributes to atherosclerosis and coronary artery diseases by inducing endothelial cell injury and dysfunction. Recent studies have provided increasing evidence that EPCs (endothelial progenitor cells) participate in ongoing endothelial repair and postnatal neovascularization. However, the changes in EPCs in patients with hypercholesterolaemia have not been elucidated to date. Therefore we investigated the number and functional activity of EPCs in patients with hypercholesterolemia. Total MNCs (mononuclear cells) were isolated from 20 patients with hypercholesterolaemia and 20 matched control subjects. EPCs were characterized as adherent cells double-positive for DiI-LDL (1,1′-dioctadecyl-3,3,3′,3′-tetramethylindocarbocyanide percholate-labelled low-density lipoprotein) uptake and lectin binding by direct fluorescent staining under a laser scanning confocal microscope, and were characterized further by demonstrating the expression of KDR (kinase insert domain-containing receptor), CD34 and AC133 by flow cytometry. Proliferation, migration and in vitro vasculogenesis activity of EPCs were assayed using the MTT [3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl-2H-tetrazolium bromide] assay, modified Boyden chamber assay and an in vitro vasculogenesis kit respectively. EPC adhesion assay was performed by replating cells on fibronectin-coated dishes and then counting the adherent cells. As a result, the number of EPCs was significantly reduced in patients with hypercholes-terolaemia compared with that in control subjects (41.8±8.7 compared with 64.5±16.6 EPCs/×200 field respectively; P<0.05). The number of EPCs was inversely correlated with total cholesterol (r=−0.659, P<0.001) and LDL-cholesterol (r=−0.611, P<0.001) levels. In addition, the functional activities of isolated EPCs, such as proliferative, migratory, adhesive and in vitro vasculogenesis capacity, were also impaired. In conclusion, the results of the present study may state a novel pathophysiological mechanism of hypercholesterolaemia: the reduction of EPCs with decreased functional activity.

Abstract: A 55-year-old man was admitted to our hospital because of chest distress, associated with activity. Two-dimensional echocardiography (2DE) demonstrated a suspected trabeculation versus false tendon of the left ventricular apex cordis but not meeting the diagnostic criteria of noncompaction of the ventricular myocardium (NVM). Threedimensional echocardiography (3DE) revealed more prominent trabeculations and deeper intertrabecular recesses of the left ventricular apex, which were consistent with the diagnostic criteria of NVM. In contrast to 2DE, 3DE provides wide, pyramid-shaped datasets that encompass the entire left ventricle. (Neth Heart J 2009;17:208–10.)