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The article discusses physicochemistry and interpretation prevalent in cell surface interactions. It outlines the influence of surface and intermolecular forces on the behavior and response of cells on surfaces. It also provides a brief overview of cell surface and its cellular adhesion to ligands. Moreover, it explores the experimental methods for measuring intermolecular forces, including surface force apparatus (SFA), s, and atomic force microscopy (AFM).

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In this article we study a Rankin-Selberg convolution of two complex variables attached to Siegel modular forms of degree 2. We establish its basic analytic properties, find its singular curves and compute some of its residues. In particular, we show that two known Dirichlet series of Rankin-Selberg type, one introduced by Maass and another by Kohnen and Skoruppa, are obtained as residues from this series of two variables. Furthermore, we define and study a collection of Rankin-Selberg convolutions for Jacobi forms of degree 1. [ABSTRACT FROM AUTHOR]

The ability to perform two tasks simultaneously is a key function of the central executive of working memory (Baddeley, 1986). This study addressed dual-task performance after diffuse very severe traumatic brain injury (TBI) (mean coma duration = 21 days, mean post-traumatic amnesia = 70 days) or prefrontal damage due to a ruptured aneurysm of the anterior communicating artery (AACA). Mean time since injury was 8 and 16 months in the TBI and the AACA group respectively. A simple visual reaction time and random number generation were used as single and dual tasks. Randomization was self-paced, to control for individual differences in speed. Both patient groups had greater reaction time decrements than controls under the dual-task condition, suggesting a divided attention deficit. In addition, patients with AACA performed significantly poorer in random generation. These results suggest that patients with AACA and with severe TBI suffer from an impairment of the central executive system. [ABSTRACT FROM AUTHOR]

An obituary is presented for Jacques Henripin, a demographer, author, college professor, and founder of the Department of Demography at the Université de Montréal in Montréal, Québec.

The hospital water environment is an important reservoir of multidrug-resistant organisms (MDROs) and presents a risk for patient safety. We assessed the effectiveness of thermal and chemical interventions on sinks contaminated with MDRO in the hospital setting. We conducted a cross-sectional assessment of MDRO contamination of sinks and toilets in 26 clinical wards of a tertiary care hospital. MDRO-contaminated sink traps were then replaced and randomized (1:1:1) to receive chemical (sodium hypochlorite), thermal disinfection (steam), or no intervention. Interventions were repeated weekly for 4 weeks. Sinks were resampled 7 days after the last intervention. The primary outcome was the proportion of decontaminated sinks. MDROs of interest were extended spectrum beta-lactamase (ESBL) producing and carbapenemase-producing Enterobacterales, and non-fermentative Gram-negative bacilli. In the cross-sectional assessment, at least one MDRO was identified in 258 (36%) of the 748 samples and in 91 (47%) of the 192 water sources. In total, 57 (42%) of the 137 sinks and 34 (62%) of the 55 toilets were contaminated with 137 different MDROs. The most common MDRO were ESBL Enterobacterales (69%, 95/137), followed by Verona Integron-Borne Metallo-β-Lactamase (VIM) carbapenemase producing Pseudomonas aeruginosa (9%, 12/137) and Citrobacter spp. (6%, 5/137). In the nested randomized trial, five of the 16 sinks (31%) in the chemical disinfection group were decontaminated, compared with 8 of 18 (44%) in the control group (OR 0.58; 95% CI, 0.14–2.32) and 9 of 17 (53%) in the thermal disinfection group (OR 1.40; 95% CI, 0.37–5.32). Our study failed to demonstrate an added benefit of repeated chemical or thermal disinfection, beyond changing sink traps, in the MDRO decontamination of sinks. Routine chlorine-based disinfection of sinks may need to be reconsidered. [ABSTRACT FROM AUTHOR]

We demonstrate the usefulness and high sensitivity of the atomic force microscope (AFM) for imaging surface dielectric properties and for potentiometry through the detection of electrostatic forces. Electric forces as small as 10-10 N have been measured, corresponding to a capacitance of 10-19 farad. The sensitivity of our AFM should ultimately allow us to detect capacitances as low as 8×10-22 F. The method enables us to detect the presence of dielectric material over Si, and to measure the voltage in a p-n junction with submicron spatial resolution. [ABSTRACT FROM AUTHOR]