Hyperfine structure determination of the 72D52state of 133Cs

The magnitude and sign of the hyperfine structure of $\text{7}{}^2\text{D}{}_{\mathrm{<mtext>5</mtext><mtext>2</mtext>}}$state of ¹³³Cs have been measured. We find the magnetic dipole coupling constant to be A = -1.7 (2) MHz.     

A Julia-Carathéodory theorem for hyperbolically monotone mappings in the Hilbert ball

We establish a Julia-Carathéodory theorem and a boundary Schwarz-Wolff lemma for hyperbolically monotone mappings in the open unit ball of a complex Hilbert space. The second author was partially supported by the Fund for the Promotion of Research at the Technion and by the Technion VPR Fund-B. and G. Greenberg Research Fund (Ottawa).     

B-transform and its application to a fish-hyacinth model

A new transform proposed by Oyelami and Ale for impulsive systems is applied to an impulsive fish-hyacinth model. A biological policy regarding the growth of the fish and the hyacinth populations is formulated.     

Optimal fleet composition and periodic routing of offshore supply vessels

The supply vessel planning problem is a maritime transportation problem faced by amongst others the energy company Statoil. A set of offshore installations requires supplies from an onshore supply depot on a regular basis, a service performed by a fleet of offshore supply vessels. The problem consists of determining the optimal fleet composition of offshore supply vessels and their corresponding weekly voyages and schedules. We present a voyage-based solution method for the supply vessel planning problem. A computational study shows how the solution method can be used to solve real-life problems. Statoil has implemented a planning tool based on the voyage-based solution method and reports significant savings.     

Design and concise synthesis of a novel type of green fluorescent protein chromophore analogue

A small molecular model compound for the green fluorescent protein chromophore was readily synthesized by a novel condensation reaction of (thio)imidate with imino-ester via an aziridine intermediate. This compound showed fluorescence in the solid and frozen solution states but not in the solution state. Its fluorescent property was successfully applied in the detection of dsDNA.     

On the number of cusps on cuspidal curves on Hirzebruch surfaces

In this article we give an upper bound for the number of cusps on a cuspidal curve on a Hirzebruch surface. We adapt the results that have been found for a similar question asked for cuspidal curves on the projective plane, and restate the results in this new setting.     

Real-time cell-microelectronic sensing of nanoparticle-induced cytotoxic effects

We report a real-time cell analysis (RTCA) sensing method of 96 electronic microwells for profiling the cytotoxicity of nanoparticles on different cell lines. The method consists of 96 microwells embedded with microelectrodes (96x E-plate) to measure impedance changes of adherent cell lines. When the testing cells change in population, adhesion, and/or morphology, the impedance at the cell–electrode interface changes to provide real-time monitoring of overall cell status. To demonstrate this technique, we used three cell lines as sensing probes: two human lung carcinoma cell lines, A549 and SK-MES-1, and a normal mammalian cell line, CHO-K1. We tested two well-characterized nanoparticles: nano-titanium dioxide (nTiO₂) and nano-silver (nAg). The three cell lines were separately seeded into 96x E-plates and treated with varying concentrations of nanoparticles (0.078–160 μg mL⁻¹). This method provides dynamic cell response profiles and temporal IC₅₀ histograms, showing concentration-, time-, particle-, and cell-dependent cytotoxicity. The 24 h and 48 h IC₅₀ values of nAg obtained using both the RTCA and the neutral red uptake (NRU) assays were in good agreement, validating the RTCA technique. The RTCA assay does not suffer interference from nTiO₂, whereas the NRU assay cannot be used due to severe interference from nTiO₂. A cytostatic response was observed in CHO-K1 cells after 24 h exposure to 40 μg mL⁻¹ nTiO₂, which was correlated with S-phase cell cycle arrest based on cell cycle analysis using flow cytometry. This suggests that the shapes of the response curves provide indicative information, directing further studies into the mode of action of the toxicant. Advantages of the RTCA technique over traditional colorimetric assays for screening the cytotoxicity of nanoparticles include minimizing interference, qualitative and quantitative cytotoxicity data, and the capability of real-time and high-throughput measurements.