Dinuclear Gold(I) Pyrrolidinedithiocarbamato Complex: Cytotoxic and Antimigratory Activities on Cancer Cells and the Use of Metal–Organic Framework

A dinuclear gold(I) pyrrolidinedithiocarbamato complex ( 1 ) with a bidentate carbene ligand has been constructed and shows potent in vitro cytotoxic activities towards cisplatin‐resistant ovarian cancer cells A2780cis. Its rigid scaffold enables a zinc(II)‐based metal–organic framework (Zn‐MOF) to be used as a carrier in facilitating the uptake and release of 1 in solutions. Instead of using a conventional dialysis approach for the drug‐release testing, in this study, a set of transwell assay‐based experiments have been designed and employed to examine the cytotoxic and antimigratory activities of 1 @Zn‐MOF towards A2780cis.     

Correlation between glass transition temperature and thermal expansion coefficients of polymers: Its interpretation and implication

A new approach pertaining to the hole and lattice theories of polymeric systems is developed to interpret the universal inverse relationship between the glass transition temperature (T_g) and the difference in thermal expansion coefficients for liquid and glassy polymers (δ α). The success of this particular theoretical consideration rests upon the familiar hypothesis of the iso-free volume state at T_g and the entropy contribution to the hole-polymer segment interaction energy. Based on the experimental data available, we have established the free volume fraction at T_g, v_g = 0.025, which is identical with the assessment of the empirical Williams-Landel-Ferry (WLF) equation for the temperature-dependence shift factor a_T. However, appreciably higher values of v_g are reported by other contemporary models. The present findings justify an alternative form of the WLF equation with the product T_g, δ α playing the role of δ α. The universality of this novel expression is demonstrated, by means of statistical analysis, to be remarkably more warrantable than its original version.     

An Adjustable Pure Dispersion Slope Compensating-Module without Center Wavelength Shift Based on Strain-Chirped Fiber Bragg Gratings

We demonstrate an adjustable pure dispersion slope compensating-module based on strain-chirped fiber Bragg gratings.The center wavelength of the module is preserved while the pure dispersion slope is tuned.     

A Lower Bound for the Dimension of Trivariate Spline Spaces

We consider trivariate C^r spline spaces of degree d defined on arbitrary tetrahedral partitions. A lower bound for the dimension of trivariate spline spaces over arbitrary tetrahedral partitions for d > r is computed. This is the first general lower bound known.     

Multiwavelength erbium-doped fiber laser employing a nonlinear optical loop mirror

A stable and broad bandwidth multiwavelength erbium-doped fiber laser is proposed and demonstrated successfully. A nonlinear optical loop mirror which induces wavelength-dependent cavity loss and behaves as an amplitude equalizer is employed to ensure stable room-temperature multiwavelength operation. Up to 50 wavelengths lasing oscillations with wavelength spacing of 0.8 nm within a 3-dB spectral range of 1562-1605 nm has been achieved. The measured power fluctuation of each wavelength is about 0.1 dB within a 2-h period.     

The design of dehydrogenase enzymes for use in a biofuel cell: the role of genetically introduced peptide tags in enzyme immobilization on electrodes.

The immobilization of the mutants of L-lactate dehydrogenase (LDH) on poly(aniline) (PANi) composite films has been investigated. Mutants possessing peptide tags of varying charge and nucleophilicity were created to probe the nature of the interaction between the protein and PANi. These results are significant for the development of a 'generic' approach to the immobilization of enzymes and other proteins.     

Dielectric properties of self‐catalytic interpenetrating polymer network based on modified bismaleimide and cyanate ester resins

Bismaleimide (BMI) resins with good thermal stability, fire resistance, low water absorption, and good retention of mechanical properties at elevated temperatures, especially in hot/wet environments, have attracted more attention in the electronic and aerospace industries. However, their relatively high dielectric constant limits their application in the aforementioned fields. In this work, a new promising approach is presented that consists of the formation of a self‐catalytic thermoset/thermoset interpenetrating polymer network. Interpenetrating polymer networks (IPNs) based on modified BMI resin (BMI/DBA) and cyanate ester (b10) were synthesized via prepolymerization followed by thermal curing. The self‐catalytic curing mechanism of BMI/DBA‐CE IPN resin systems was examined by differential scanning calorimetry. The dielectric properties of the cured BMI/DBA‐CE IPN resin systems were evaluated by a dielectric analyzer and shown in dielectric properties‐temperature‐log frequency three‐dimensional plots. The effect of temperature and frequency on the dielectric constant of the cured BMI/DBA‐CE IPN resin systems is discussed. The composition effect on the dielectric constant of the cured IPN resin systems was analyzed on the basis of Maxwell's equation and rule of mixture. The obtained BMI/DBA‐CE IPN resin systems have the combined advantages of low dielectric constant and loss, high‐temperature resistance, and good processability, which have many applications in the microelectronic and aerospace industries. © 2003 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 41: 1123–1134, 2003     

Amplification and Compression of Ultrashort Fundamental Solitons in An Erbium-Doped Nonlinear Amplifying Fiber Loop Mirror

A nonlinear amplifying loop mirror constructed from erbium-doped fiber is proposed for simultaneous amplification and compression of ultrashort fundamental solitons. Numerical simulations show that, the proposed device performs efficient high-quality amplification and compression of solitons.     

Enhanced cycling stability of o-LiMnO2 cathode modified by lithium boron oxide coating for lithium-ion batteries

The effect of lithium boron oxide (LBO) coating on the electrochemical performance of orthorhombic LiMnO₂ (o-LiMnO₂) cathode for lithium-ion batteries is investigated. o-LiMnO₂ synthesized via solid state synthesis technique is modified with LBO addition. The presence of LBO is identified via Fourier transform infrared spectroscopy analysis. o-LiMnO₂ is observed to transform to a spinel-like phase during cycling which undergoes capacity fading. Studies indicate that the presence of 1–2 wt% LBO results in an improved capacity and better capacity retention with cycling. The pristine sample reveals a maximum specific capacity of 172 mAhg^?1, whereas the LBO-modified samples display about 189.1 mAhg^?1 in the cycling tests conducted at a rate of 50 mAg^?1 in the voltage range of 2–4.5 V. After 70 cycles, the LBO-modified LiMnO₂ displayed higher capacity retention of 175 mAhg^?1 as compared to the pristine sample that exhibited 130 mAhg^?1. By analyzing the charge–discharge behavior, it is observed that the capacity obtained from lithium insertion into the tetrahedral sites of the spinel structure is more or less constant throughout the cycling and that the bulk of the capacity loss is resulting when lithium is inserted into the octahedral sites of the spinel structure. Impedance measurement reveals a reduced charge-transfer resistance for the LBO-modified samples suggesting that the presence of LBO is countering capacity loss arising from insertion of lithium into the octahedral sites thus contributing to the overall cycling stability.     

Selective Inhibition of Lysine‐Specific Demethylase 5A (KDM5A) Using a Rhodium(III) Complex for Triple‐Negative Breast Cancer Therapy

Lysine‐specific demethylase 5A (KDM5A) has recently become a promising target for epigenetic therapy. In this study, we designed and synthesized metal complexes bearing ligands with reported demethylase and p27 modulating activities. The Rh(III) complex 1 was identified as a direct, selective and potent inhibitor of KDM5A that directly abrogate KDM5A demethylase activity via antagonizing the KDM5A‐tri‐/di‐methylated histone 3 protein–protein interaction (PPI) in vitro and in cellulo. Complex 1 induced accumulation of H3K4me3 and H3K4me2 levels in cells, causing growth arrest at G1 phase in the triple‐negative breast cancer (TNBC) cell lines, MDA‐MB‐231 and 4T1. Finally, 1 exhibited potent anti‐tumor activity against TNBC xenografts in an in vivo mouse model, presumably via targeting of KDM5A and hence upregulating p27. Moreover, complex 1 was less toxic compared with two clinical drugs, cisplatin and doxorubicin. To our knowledge, complex 1 is the first metal‐based KDM5A inhibitor reported in the literature. We anticipate that complex 1 may be used as a novel scaffold for the further development of more potent epigenetic agents against cancers, including TNBC.