Endohedral Metallofullerene Derivatives

Trimetallic nitride endohedral metallofullerene derivatives and their preparation are described. The trimetallic nitride endohedral metallofullerene derivatives have the general formula A(sub 3-n)X(sub n)@C(sub m)(R) where n ranges from 0 to 3, A and X may be trivalent metals and may be either rare earth metal or group IIIB metals, m is between about 60 and about 200, and R is preferably an organic group. Derivatives where the R group forms cyclized derivatives with the fullerene cage are also described

Encapsulated Molecules in Carbon Nanotubes: Structure and Properties

We encapsulate a number of fullerenes inside single-walled carbon nanotubes (SWNTs) including La2@C80 and ErxSc3-xN@C80(x=0-3). The structural properties of these nanoscopic hybrid materials are described using high resolution transmission electron microscopy and electron diffraction. It is found that the encapsulated fullerenes selfassemble into long, one-dimensional chains. The thermal stability of these supramolecular assemblies are studied and large variations are found. The behavior is nominally consistent with the mass of the encapsulated metallofullerenes

High Blocking Temperature of Magnetization and Giant Coercivity in the Azafullerene Tb 2 @C 79 N with a Single-Electron Terbium–Terbium Bond

The azafullerene Tb 2 @C 79 N is found to be a single-molecule magnet with a high 100-s blocking temperature of magnetization of 24 K and large coercivity. Tb magnetic moments with an easy-axis single-ion magnetic anisotropy are strongly coupled by the unpaired spin of the single-electron Tb−Tb bond. Relaxation of magnetization in Tb 2 @C 79 N below 15 K proceeds via quantum tunneling of magnetization with the characteristic time τ QTM =16 462±1230 s. At higher temperature, relaxation follows the Orbach mechanism with a barrier of 757±4 K, corresponding to the excited states, in which one of the Tb spins is flipped. © 2019 The Authors. Published by Wiley-VCH Verlag GmbH & Co. KGaA

Optimization of Control Strategies for Non-Domiciliated Triatoma dimidiata, Chagas Disease Vector in the Yucatán Peninsula, Mexico

Chagas disease is the most important vector-borne disease in Latin America. Residual insecticide spraying has been used successfully for the elimination of domestic vectors in many regions. However, some vectors of non-domestic origin are able to invade houses, and they are now a key challenge for further disease control. We developed a mathematical model to predict the temporal variations in abundance of non-domiciliated vectors inside houses, based on triatomine demographic parameters. The reliability of the predictions was demonstrated by comparing these with different sets of insect collection data from the Yucatan peninsula, Mexico. We then simulated vector control strategies based on insecticide spraying, insect, screens and bednets to evaluate their efficacy at reducing triatomine abundance in the houses. An optimum reduction in bug abundance by at least 80% could be obtained by insecticide application only when doses of at least 50 mg/m2 were applied every year within a two-month period matching the house invasion season by bugs. Alternatively, the use of insect screens consistently reduced bug abundance in the houses and offers a sustainable alternative. Such screens may be part of novel interventions for the integrated control of various vector-borne diseases

Expedition Inspiration Fund for Breast Cancer Research Meeting 2003

Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/44216/1/10549_2004_Article_5139058.pd

Characterization of the Dispersal of Non-Domiciliated Triatoma dimidiata through the Selection of Spatially Explicit Models

Chagas disease is one of the most important neglected diseases in Latin America. Although insecticides have been successfully sprayed to control domiciliated vector populations, this strategy has proven to be ineffective in areas where non-domiciliated vectors immigrating from peridomestic or sylvatic ecotopes can (re-)infest houses. The development of strategies for the control of non-domiciliated vectors has thus been identified by the World Health Organization as a major challenge. Such development primarily requires a description of the spatio-temporal dynamics of infestation by these vectors, and a good understanding of their dispersal. We combined for the first time extensive spatio-temporal data sets describing house infestation dynamics by Triatoma dimidiata inside one village, and spatially explicit population dynamics models. The models fitted and predicted remarkably the observed infestation dynamics. They thus provided both key insights into the dispersal of T. dimidiata in this area, and a suitable mathematical background to evaluate the efficacy of various control strategies. Interestingly, the observed and modelled patterns of infestation suggest that interventions could focus on the periphery of the village, where there is the highest risk of transmission. Such spatial optimization may allow for reducing the cost of control, compensating for repeated interventions necessary for non-domiciliated vectors

Polarizability Effects Dominate the Chromatographic Retention Behavior of Spheroidal and Elipsoidal Metallofullerene Nanospheres

The chromatographic retention behavior of spherical and elipsodial metallofullerenes provides a unique class for studying subtle intermolecular dispersive (London effect) and inductive (Debye effect) solution-state/solid-phase interactions. The known trimetallic nitride endohedral metallofullerene A₃N@C₈₀ isomers are nearly spherical A₃N@C₈₀-<i>I</i>_<i>h</i> and ellipsoidal A₃N@C₈₀-<i>D</i>_5<i>h</i>. These metallofullerene isomers are readily available with group IIIB and lanthanide trimetallic nitride clusters (A₃N)⁶⁺. In the current study, chromatographic HPLC retention behavior is monitored for two different HPLC stationary phases, pentabromobenzyl and pyrenylethyl and augmented by density functional theory computational results. Although dipole moments, lanthanide contraction, and charge transfer from the internal cluster (A₃N)⁶⁺ are important factors controlling chromatographic retention, our results suggest that the fullerene cage polarizability is the dominant factor controlling chromatographic separation of A₃N@C₈₀-<i>I</i>_<i>h</i> and elipsodial A₃N@C₈₀-<i>D</i>_5<i>h</i> isomers. Our study suggests that computational dipole moment and polarizability data allow accurate prediction of chromatographic retention behavior for fullerenes and metallofullerenes and can be extended to other π conjugated aromatic systems

Structure and proposed drug release mechanism of NsiL.

<p>a, in serum; b, in tumor cells.</p

Size distribution of different nanoparticles.

<p>PEGylated DSPC lipsome (black), SWNH(-CH₂-CH₂-COOH)_x (red), paclitaxel loaded SWNH(-CH₂-CH₂-COOH)_x (green), DSPC NsiL (blue), and DSPC NsiL without paclitaxel (light blue). Sizes are shown in diameters (mean ± S.D., n = 45).</p

Properties of lipid used in NsiL immunoliposome formulation.

<p>Properties of lipid used in NsiL immunoliposome formulation.</p