Induction of human breast cancer cell apoptosis from G2/M preceded by stimulation into the cell cycle by Z-1,1-dichloro-2,3-diphenylcyclopropane

We have shown previously that Z-1,1-dichloro-2,3-diphenylcyclopropane (a.k.a. Analog II, A(II)) inhibits human breast cancer cell proliferation regardless of estrogen receptor status or estrogen sensitivity, and that its cellular targets include microtubules. In the present study, we investigated the apoptosis-inducing effects of A(II). MCF-7, MCF-7/LY2, and MDA-MB-231 cells all showed nuclear fragmentation in response to 100 microM A(II) when stained with Hoechst 33342 and examined by fluorescence microscopy. Pulsed field gel electrophoretic analysis showed that each of the cell lines also developed specific high molecular weight DNA fragments: a low level of 1-2 Mb fragments appeared after 6 hr, while 30-50 kb fragments accumulated subsequently. At 24 hr of drug exposure, the majority of cells became nonadherent, and the 30-50 kb fragments were restricted to detached MCF-7 and MDA-MB-231 cells. Both adherent and detached MCF-7/LY2 cells exhibited these fragments. A previous study by single-color (propidium) flow cytometry demonstrated that A(II) blocks MDA-MB-231 cells in G2/M of the cell cycle. More refined analyses in the present study showed this same result for MDA-MB-231 cells, but MCF-7 and MCF-7/LY2 cells did not reveal apparent drug-induced cell cycle block. A(II) demonstrated growth inhibitory, cell cycle-perturbing, and hypodiploidy-inducing activity against other human breast carcinoma lines, i.e. BT-20, CAMA-1, and SKBR-3, but no such actions in the non-tumorigenic, "normal" human breast epithelial line MCF-10A. Bromodeoxyuridine labeling and two-color flow cytometric analysis, however, suggested that A(II) caused stimulation into S phase, and that G2/M was the phase of the cell cycle from which cells apoptosed. A(II) caused cell rounding, detachment from the growth matrix, and nuclear shrinkage and fragmentation in parallel with biochemical changes. Cycloheximide inhibited A(II)-induced cell death, indicating that its toxicity requires de novo protein synthesis.     

Experimental Electrohydrodynamic Nanospray Production Using Drawn Glass Capillaries

This article describes a simple and low-cost method of fabricating glass capillary nanospray emitter sources, and, if required, inserting a charging electrode. Initial experimental work employing such a source is described, whose results suggest that whilst the positioning of the charging electrode relative to the orifice influences the charging current and spray considerably, this position may not correspond with that previously reported as being ideal for electrospray systems one or two orders of magnitude greater.     

Fabrication and Electromechanical Characterization of Silver-Clad BSCCO Tapes

The powder-in-tube technique consisting of industrial processes such as wire drawing and rolling has been widely used to fabricate superconducting tapes. In the present investigation a novel technique was adopted to fabricate BSCCO 2223 tapes. Instead of wire drawing, the silver billet was reduced in size by groove rolling. Stress conditions during groove rolling were analyzed and appropriate changes were incorporated to optimize the deformation process. Subsequent thermomechanical treatment resulted in tapes with average critical current densities of 18,000 A/cm². Phase development and microstructural evolution during the thermomechanical treatment were studied using XRD, SEM, and TEM. The electromechanical properties of monofilament and composite BSCCO tapes were evaluated by subjecting them to in situ tensile tests. The strain tolerance of the composite was found to be better than that of the monofilament BSCCO tape.     

Controllability of stochastic integrodifferential systems

In this paper sufficient conditions for the complete controllability of a stochastic semilinear integrodifferential system in finite dimensional spaces are established using the resolvent matrix and the Banach fixed point theorem. An example is provided to illustrate the result.     

Doped oxides of cerium as inorganic colorants

The colour of inorganic colorants is based on metal ions such as cadmium, lead, chromium or cobalt, the majority of which are unfortunately potentially toxic. Thus, there is in a need to introduce alternative metal or metal oxides, which would be environmentally friendly and economically viable as a replacement for potentially toxic inorganic colorants. Rare earth-based colorants offer an additional opportunity for the development of optically pure colours. In this study, a replacement for potentially toxic colorants has been sought through the use of a rare earth metal ion, cerium. Appropriate doping of cerium oxides with molybdenum and iron gives an orange–red colorant. The conditions ideal for optimal colour have been standardised and the resultant colorant characterised through powder X-ray diffraction techniques, particle size measurement, etc. The colorants exhibit good hiding power and tinting strength.     

NON-WETTING ELECTROSTATIC ASSISTED NOZZLE FOR SPRAYING A CATALYTIC MELT

In this paper we present how a normal pressure nozzle can be adapted into a successful electrostatic assisted atomiser for one particular industrial application. The “Reverse Modelling” technique for the design of the nozzle head, induction electrode and counter 'wetting' electrode using finite element method is of universal value and can be used widely in induction charging electrostatic spraying applications where wetting is a problem. Experimental results showed that under the same operating condition, an optimised geometry and position of electrodes can give a spray current an order of magnitude higher than the previous design without any wetting problem. An optimum combination of an induction and a counter electrode geometry and positions will ensure a non-wetting induction nozzle assembly with very high charging efficiency.     

Optimized CdTe sensors for measurement of electric and magneticfields in the near-field region

We present novel electric and magnetic field measurement systems utilizing optical technologies, which have been developed, tested, and calibrated in the frequency region up to 2 GHz. They show an advantage over currently available measurement systems in that they are passive, all-dielectric, and EM immune. A detailed analysis of field perturbation by the measuring probes in the near-field region was performed using finite-difference time-domain (FDTD) algorithm for solving Maxwell's equations. Both probes were calibrated using a gigahertz transversal electric and magnetic cell, and the results show a linear response     

The influence of MWCNT and hybrid (MWCNT/nanoclay) fillers on performance of EPDM-CIIR blends in nuclear applications: Mechanical,hydrocarbon transport,and gamma-radiation aging characteristics

Blends of EPDM and chlorobutyl (CIIR) rubbers are used in nuclear plants where they have to withstand the combined effect of radiation and hydrocarbon aging. To improve their mechanical properties as well as hydrocarbon and gamma radiation resistance, the blends are reinforced with 0.5, 1, 1.5, and 2 phr of MWCNT. The increase in mechanical properties was highest for 1.5 phr MWCNT with 69% increase in tensile strength. The improvement in properties was correlated to MWCNT dispersion and filler–polymer interactions, which were confirmed by TEM and FTIR analysis. Hydrocarbon transport coefficients decreased on addition of MWCNT. The nanocomposites were exposed to 0.5, 1, and 2 MGy cumulative doses of gamma radiation. Depending on the radiation dose, crosslinking and/or chain scission occurred causes changes in physical properties. MWCNT reinforcement reduced the magnitude of changes in mechanical and transport properties after γ-irradiation. ESR and FTIR spectra provided qualitative information on free radical formation and chemical changes due to γ-rays exposure. To further enhance the properties, hybrid nanocomposites with 1.5 phr MWCNT and varying nanoclay contents (0.5, 1, 1.5, 2, and 5 phr) were prepared. Due to synergism between MWCNT and nanoclay, the hybrid composites had superior properties with hybrid containing 5 phr nanoclay giving 98% increase in tensile strength.     

Rapid detection of Salmonella in pet food: design and evaluation of integrated methods based on real-time PCR detection

Reducing the risk of Salmonella contamination in pet food is critical for both companion animals and humans, and its importance is reflected by the substantial increase in the demand for pathogen testing. Accurate and rapid detection of foodborne pathogens improves food safety, protects the public health, and benefits food producers by assuring product quality while facilitating product release in a timely manner. Traditional culture-based methods for Salmonella screening are laborious and can take 5 to 7 days to obtain definitive results. In this study, we developed two methods for the detection of low levels of Salmonella in pet food using real-time PCR: (i) detection of Salmonella in 25 g of dried pet food in less than 14 h with an automated magnetic bead-based nucleic acid extraction method and (ii) detection of Salmonella in 375 g of composite dry pet food matrix in less than 24 h with a manual centrifugation-based nucleic acid preparation method. Both methods included a preclarification step using a novel protocol that removes food matrix-associated debris and PCR inhibitors and improves the sensitivity of detection. Validation studies revealed no significant differences between the two real-time PCR methods and the standard U.S. Food and Drug Administration Bacteriological Analytical Manual (chapter 5) culture confirmation method.     

Delay analysis of selective-repeat ARQ with applications to link adaptation in wireless packet data systems

Radio link control (RLC) protocols are typically employed for reliable in-sequence delivery of service data units (SDUs) in wireless packet data systems. The RLC layer segments packets obtained from the upper layer (referred to as SDUs) into smaller RLC transmission units (or blocks) and uses selective-repeat automatic repeat request (SR-ARQ) for error recovery of RLC blocks. In earlier work, SR-ARQ performance is typically characterized in terms of the long-term throughput or in-sequence delivery delay of RLC blocks. The SDU delivery delay which is a more meaningful measure of RLC performance (in terms of the service provided to a higher layer, e.g., transmission control protocol) has not been quantified. In this paper, we analyze the SDU delivery delay of SR-ARQ as a function of the SDU size and the channel coding scheme employed. Closed-form delay expressions as well as approximations are provided. The analysis is verified through enhanced general packet radio service RLC simulations. Based on the analysis, we propose that link adaptation be backlog dependent in order to reduce the SDU delivery delay at the RLC layer.