Changes in Hyaluronan Metabolism and RHAMM Receptor Expression Accompany Formation of Complicated Carotid Lesions and May be Pro-Angiogenic Mediators of Intimal Neovessel Growth.

Previous studies have shown that changes in expression of the glycosaminoglycan, hyaluronan (HA) were associated with erosion in areas of post-mortem coronary artery liable to rupture. Angiogenesis is an important feature of ulcerating haemorrhagic plaques prone to rupture. HA is a glycosaminoglycan known to possess potent angiogenic properties on metabolism to oligosaccharides of HA (o-HA) in the presence of hyaluronidase (HYAL) enzymes. In this study, we have examined HA receptor and HYAL enzyme expression in a series of carotid artery specimens used as vascular transplants and exhibiting various stages of atherosclerotic lesions as determined by anatomo-pathology. Our results demonstrated dramatically increased expression of HYAL-1 in regions of inflammation associated with complicated plaques. Receptor for HA-mediated motility (RHAMM), which is known to be important in transducing angiogenic signals in vascular endothelium, was strongly expressed on intimal blood vessels from complicated lesions but almost absent from other regions including adventitial vessels. Metabolism of HA, together with up-regulation of RHAMM in complicated plaque lesions might be partly responsible for over-production of leaky neovessels and predisposition to plaque rupture

Intermolecular Bonding of Hemin in Solution and in Solid State Probed by N K-edge X-ray Spectroscopies

X-ray absorption/emission spectroscopy (XAS/XES) at the N K-edge of iron protoporphyrin IX chloride (FePPIX-Cl, or hemin) has been carried out for dissolved monomers in DMSO, dimers in water and for the solid state. This sequence of samples permits identification of characteristic spectral features associated with the hemin intermolecular bonding. These characteristic features are further analyzed and understood at the molecular orbital (MO) level based on the DFT calculations

Magnetic Properties of FePt Nanoparticles Prepared by a Micellar Method

FePt nanoparticles with average size of 9 nm were synthesized using a diblock polymer micellar method combined with plasma treatment. To prevent from oxidation under ambient conditions, immediately after plasma treatment, the FePt nanoparticle arrays were in situ transferred into the film-growth chamber where they were covered by an SiO2 overlayer. A nearly complete transformation of L10 FePt was achieved for samples annealed at temperatures above 700 °C. The well control on the FePt stoichiometry and avoidance from surface oxidation largely enhanced the coercivity, and a value as high as 10 kOe was obtained in this study. An evaluation of magnetic interactions was made using the so-called isothermal remanence (IRM) and dc-demagnetization (DCD) remanence curves and Kelly–Henkel plots (ΔM measurement). The ΔM measurement reveals that the resultant FePt nanoparticles exhibit a rather weak interparticle dipolar coupling, and the absence of interparticle exchange interaction suggests no significant particle agglomeration occurred during the post-annealing. Additionally, a slight parallel magnetic anisotropy was also observed. The results indicate the micellar method has a high potential in preparing FePt nanoparticle arrays used for ultrahigh density recording media

Tetrabenzoporphyrin and -mono-, - Cis -di- and tetrabenzotriazaporphyrin derivatives: Electrochemical and spectroscopic implications of meso CH Group replacement with nitrogen

Nonperipherally hexyl-substituted metal-free tetrabenzoporphyrin (2H-TBP, 1a) tetrabenzomonoazaporphyrin (2H-TBMAP, 2a), tetrabenzo-cis-diazaporphyrin (2H-TBDAP, 3a), tetrabenzotriazaporphyrin (2H-TBTAP, 4a), and phthalocyanine (2H-Pc, 5a), as well as their copper complexes (1b-5b), were synthesized. As the number of meso nitrogen atoms increases from zero to four, Îmax of the Q-band absorption peak becomes red-shifted by almost 100 nm, and extinction coefficients increased at least threefold. Simultaneously the blue-shifted Soret (UV) band substantially decreased in intensity. These changes were related to the relative electron-density of each macrocycle expressed as the group electronegativity sum of all meso N and CH atom groups, âχR. X-ray photoelectron spectroscopy differentiated between the three different types of macrocyclic nitrogen atoms (the Ninner, (NH)inner, and Nmeso) in the metal-free complexes. Binding energies of the Nmeso and Ninner,Cu atoms in copper chelates could not be resolved. Copper insertion lowered especially the cathodic redox potentials, while all four observed redox processes occurred at larger potentials as the number of meso nitrogens increased. Computational chemical methods using density functional theory confirmed 1b to exhibit a Cu(II) reduction prior to ring-based reductions, while for 2b, Cu(II) reduction is the first reductive step only if the nonperipheral substituents are hydrogen. When they are methyl groups, it is the second reduction process; when they are ethyl, propyl, or hexyl, it becomes the third reductive process. Spectro-electrochemical measurements showed redox processes were associated with a substantial change in intensity of at least two main absorbances (the Q and Soret bands) in the UV spectra of these compounds

Confinement increases the lifetimes of hydroxyapatite precursors

The mineral component of bone is a carbonated, nonstoichiometric hydroxyapatite (calcium phosphate) that forms in nanometer confinement within collagen fibrils, the principal organic constituent of bone. We here employ a model system to study the effects of confinement on hydroxyapatite precipitation from solution under physiological conditions. In common with earlier studies of calcium carbonate and calcium sulfate precipitation, we find that confinement significantly prolongs the lifetime of metastable phases, here amorphous calcium phosphate (ACP) and octacalcium phosphate (OCP). The effect occurs at surprisingly large separations of up to 1 μm, and at 0.2 μm the lifetime of ACP is extended by at least an order of magnitude. The soluble additive poly(aspartic acid), which in bulk stabilizes ACP, appears to act synergistically with confinement to give a greatly enhanced stability of ACP. The reason for the extended lifetime appears to be different from that found with CaCO3 and CaSO4, and underscores both the variety of mechanisms whereby confinement affects the growth and transformation of solid phases, and the necessity to study a wide range of crystalline systems to build a full understanding of confinement effects. We suggest that in the case of ACP and OCP the extended lifetime of these metastable phases is chiefly due to a slower transport of ions between a dissolving metastable phase, and the more stable, growing phase. These results highlight the potential importance of confinement on biomineralization processes

Unmet need for family planning among married women of reproductive age group in urban Tamil Nadu

Context: Unmet need for family planning (FP), which refers to the condition in which there is the desire to avoid or post-pone child bearing, without the use of any means of contraception, has been a core concept in the field of international population for more than three decades. Objectives: The very objective of this study is to determine the prevalence of "unmet need for FP" and its socio-demographic determinants among married reproductive age group women in Chidambaram. Materials and Methods: The study was a community-based cross-sectional study of married women of the reproductive age group, between 15 and 49 years. The sample size required was 700. The cluster sampling method was adopted. Unmarried, separated, divorced and widows were excluded. Results: The prevalence of unmet need for FP was 39%, with spacing as 12% and limiting as 27%. The major reason for unmet need for FP among the married group was 18%, for low perceived risk of pregnancy, 9%, feared the side effects of contraception 5% lacked information on contraceptives, 4% had husbands who opposed it and 3% gave medical reasons. Higher education, late marriage, more than the desired family size, poor knowledge of FP, poor informed choice in FP and poor male participation were found to be associated with high unmet need for FP. Conclusion: Unmet need for younger women was spacing of births, whereas for older women, it was a limitation of births. Efforts should be made to identify the issues in a case by case approach. Male participation in reproductive issues should be addressed

Resilience strategies to recover from the cascading ripple effect in a copper supply chain through project management

As the supply chains are growing and becoming more interdependent, the vulnerability and the chances of supply chain failure also increases. The supply chain industry is severely affected due to the COVID-19 outbreak and industry practitioners are focusing on minimizing the ripple effect of the disruption made to the economy. Considering the unprecedented situation, the research is motivated to analyse the ripple effect in a multi-echelon supply chain and investigate the performance at various nodes to understand the capability of the supply chain to withstand the disruptions at different levels. Using discrete event simulation, this study analyses the ripple effect in the copper industry by an agent-based simulation software anyLogistix, considering various key performance indexes (KPIs) to gauge the magnitude. From the results of the simulation, it is evident that the lack of safety stocks and multi-sourcing of copper facilitate as major causes for the disruptions. The simulation helps to understand the disruption levels and make the supply chain more resilient and robust for any future disruption. Further, the study proposes resilient project management solutions to recover from the cascading ripple effect in the copper supply chain. The scientific contribution of the research is to provide supply chain managers with simulation techniques to understand the ripple effect on the copper supply chain. It helps the stakeholders to understand the importance of project management tools to reduce the cascading ripple effect in a copper supply chain. Further, the findings of this study will support contemporary managers, supply chain allies, project managers, and stakeholders to formulate strategies for recovering from the supply chain disruptions caused due to natural disasters, pandemics such as COVID-19