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The US Department of Agriculture, Food Safety Inspection Service (USDA-FSIS) considers mechanically-tenderized beef as "non-intact" and a food safety concern because of the potential for translocation of surface Escherichia coli O157:H7 into the interior of the meat that may be cooked "rare or medium-rare" and consumed. We evaluated 14 potential spray interventions on E. coli O157:H7-inoculated lean beef wafers (~106 CFU/cm², n = 896) passing through a spray system (18 s dwell time, ~40 pounds per square inch, PSI) integrated into the front end of a Ross TC-700MC tenderizer. Inoculated and processed beef wafers were stomached with D/E neutralizing broth and plated immediately, or were held in refrigerated storage for 1-, 7-, or 14-days prior to microbial enumeration. Seven antimicrobials that showed better performance in preliminary screening on beef wafers were selected for further testing on beef subprimals in conjunction with blade tenderization. Boneless top sirloin beef subprimals were inoculated at ~2 × 104 CFU/cm² with a four-strain cocktail of E. coli O157:H7 and passed once, lean side up, through an integrated spray system and blade tenderizer. Core samples obtained from each subprimal were examined for the presence/absence of E. coli O157:H7. The absence of E. coli O157:H7 in core samples correlated with the ability of the antimicrobials to reduce bacterial levels on the surface of beef prior to blade tenderization.

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Social media and specifically podcasting are available to the field of nurse anesthesia as potential educational tools. This article outlines key concepts in social media, including free open access medical education and literature supporting the use of podcasting in higher, medical, and nursing education. The authors provide an educational model useful for developing social media tools and a logic model for producing an educational podcast. These tools were used in the production of the authors' educational anesthesia podcast, and key steps are outlined. The goal of this article is to provide an overview of social media and relevant resources so that other educational podcasts may be developed for the nurse anesthesia community.

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Modular oxacyclophanes featuring m-terphenyl units scaffold inter-pi-system interaction in face-to-face stacked or orthogonal orientations, leading to distinct photophysical properties.

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Two poly(p-phenylenevinylene) derivative alternating copolymers (P1-I and P2-I) have been prepared featuring iodo substituents and m-phenylene units to periodically disrupt conjugation. P1-I was derivatized with various chromophores to yield P1a-f. In P1a-f, the chromophores were positioned within a sterically protected pocket shielding them from interchain interactions so that intrachain interactions between polymer segments could be observed. Solution and film properties of polymers have been examined. Post-polymerization chromophore modification leads to new photophysical properties such as intramolecular charge transfer and fluorescent resonance energy transfer processes in some cases.

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The terphspan scaffold was employed to support a bis(N-heterocyclic carbene) ligand () that provides a m-terphenyl canopy over one side of its metal complexes. Single-crystal X-ray diffraction studies on a silver complex of {[Ag()]AgBr(2)}(2) revealed an unusual tetranuclear silver core with a Ag-Ag bond distance of 3.0241(8) A with as a trans-chelating ligand (C-Ag-C = 171 degrees ). A preliminary X-ray structure of pseudo-square planar [PdCl(2)()] showed a similar binding mode of (C-Pd-C = 177 degrees ). High yields were obtained in Suzuki-Miyaura coupling reactions utilizing [PdCl(2)()] as the procatalyst and the results were compared with analogous complexes of trans-spanning diphosphine () and diphosphinite () complexes. The diphosphinite complex, [PdCl(2)()], decomposes to [mu-ClPd(PPh(2)OH)(PPh(2)O)](2) at room temperature.

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A sterically encumbered m-terphenyl oxacyclophane substituted with two aryl iodide substituents has been prepared as a versatile monomer for the preparation of π-conjugated polymers. The monomer has been used to prepare a poly(p-phenylene ethynylene) derivative (P1) incorporating oxacyclophane units as canopies that shield one side of the π-system from inter-chain interactions. The photophysical properties of P1 in dilute solution compare well to those of a poly(p-phenylene ethynylene) derivative (P2) that lacks the canopy. The presence of the steric canopy leads to a diminished inter-chain interaction in the solid state and enhances the kinetic response of P1 to vapors of nitro-organics such as TNT, presumably by increasing the permeability of P1 to these analytes over that of P2.

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A dizinc phosphohydrolase enzyme model complex employing the dinucleating ligand 2,6-bis-[(bis-pyridin-2-ylmethyl-amino)methyl]-4-methylphenol (L1) was tested for binding to a series of 11 commercially available complexometric indicators in aqueous N-2-hydroxyethylpiperazine-N'-2-ethanesulfonic acid (HEPES) buffer at pH 7.4, with the aim of determining the applicability of these indicators in indicator displacement assays (IDAs) under physiological conditions. Dissociation constants (Kd) were determined for 11 indicator-Zn2L1 complexes, spanning 2 orders of magnitude from 2.8 x 10(-4) M (alizarin red S) to 2.7 x 10(-6) M (bromo pyrogallol red). Phosphate and pyrophosphate were tested for their ability to displace bound indicator and produce a detectable colorimetric response. Three indicators (bromo pyrogallol red, mordant blue 9, and zincon) complex to Zn2L1 to form an indicator displacement assay selective for pyrophosphate over phosphate. Because selection of an indicator/analyte pair having appropriate relative Kd values is critical for their successful application in IDAs, the binding data for these 11 indicators should assist their extension to IDAs for other analytes.

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Kinesins from the bipolar (Kinesin-5) family are conserved in eukaryotic organisms and play critical roles during the earliest stages of mitosis to mediate spindle pole body separation and formation of a bipolar mitotic spindle. To date, genes encoding bipolar kinesins have been reported to be essential in all organisms studied. We report the characterization of CaKip1p, the sole member of this family in the human pathogenic yeast Candida albicans. C. albicans Kip1p appears to localize to the mitotic spindle and loss of CaKip1p function interferes with normal progression through mitosis. Inducible excision of CaKIP1 revealed phenotypes unique to C. albicans, including viable homozygous Cakip1 mutants and an aberrant spindle morphology in which multiple spindle poles accumulate in close proximity to each other. Expression of the C. albicans Kip1 motor domain in Escherichia coli produced a protein with microtubule-stimulated ATPase activity that was inhibited by an aminobenzothiazole (ABT) compound in an ATP-competitive fashion. This inhibition results in 'rigor-like', tight association with microtubules in vitro. Upon treatment of C. albicans cells with the ABT compound, cells were killed, and terminal phenotype analysis revealed an aberrant spindle morphology similar to that induced by loss of the CaKIP1 gene. The ABT compound discovered is the first example of a fungal spindle inhibitor targeted to a mitotic kinesin. Our results also show that the non-essential nature and implementation of the bipolar motor in C. albicans differs from that seen in other organisms, and suggest that inhibitors of a non-essential mitotic kinesin may offer promise as cidal agents for antifungal drug discovery.

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The rate constant for Cl + NH3 --> HCl + NH2 has been measured over 290-570 K by the time-resolved resonance fluorescence technique. Ground-state Cl atoms were generated by 193 nm excimer laser photolysis of CCl4 and reacted under pseudo-first-order conditions with excess NH3. The forward rate constant was fit by the expression k1 = (1.08 +/- 0.05) x 10(-11) exp(-11.47 +/- 0.16 kJ mol(-1)/RT) cm3 molecule(-1) s(-1), where the uncertainties in the Arrhenius parameters are +/-1 sigma and the 95% confidence limits for k1 are +/-11%. To rationalize the activation energy, which is 7.4 kJ mol(-1) below the endothermicity in the middle of the 1/T range, the potential energy surface was characterized with MPWB1K/6-31++G(2df,2p) theory. The products NH2 + HCl form a hydrogen-bonded adduct, separated from Cl + NH3 by a transition state lower in energy than the products. The rate constant for the reverse process k(-1) was derived via modified transition state theory, and the computed k(-1) exhibits a negative activation energy, which in combination with the experimental equilibrium constant yields k1 in fair accord with experiment.