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The essential organization of microtubules within neurons has been described; however, less is known about how neuronal actin is arranged and the functional implications of its arrangement. Here, we describe, in live cells, an actin-based structure in the proximal axon that selectively prevents some proteins from entering the axon while allowing the passage of others. Concentrated patches of actin in proximal axons are present shortly after axonal specification in rat and zebrafish neurons imaged live, and they mark positions where anterogradely traveling vesicles carrying dendritic proteins halt and reverse. Patches colocalize with the ARP2/3 complex, and when ARP2/3-mediated nucleation is blocked, a dendritic protein mislocalizes to the axon. Patches are highly dynamic, with few persisting longer than 30 min. In neurons in culture and in vivo, actin appears to form a contiguous, semipermeable barrier, despite its apparently sparse distribution, preventing axonal localization of constitutively active myosin Va but not myosin VI.

We improve multiphoton structured illumination microscopy using a nonlinear guide star to determine optical aberrations and a deformable mirror to correct them. We demonstrate our method on bead phantoms, cells in collagen gels, nematode larvae and embryos, Drosophila brain, and zebrafish embryos. Peak intensity is increased (up to 40-fold) and resolution recovered (up to 176 ± 10 nm laterally, 729 ± 39 nm axially) at depths ∼250 μm from the coverslip surface.

Although neuronal activity can be modulated using a variety of techniques, there are currently few methods for controlling neuronal connectivity. We introduce a tool (GFE3) that mediates the fast, specific and reversible elimination of inhibitory synaptic inputs onto genetically determined neurons. GFE3 is a fusion between an E3 ligase, which mediates the ubiquitination and rapid degradation of proteins, and a recombinant, antibody-like protein (FingR) that binds to gephyrin. Expression of GFE3 leads to a strong and specific reduction of gephyrin in culture or in vivo and to a substantial decrease in phasic inhibition onto cells that express GFE3. By temporarily expressing GFE3 we showed that inhibitory synapses regrow following ablation. Thus, we have created a simple, reversible method for modulating inhibitory synaptic input onto genetically determined cells.

To address the need for a bright, photostable labeling tool that allows long-term in vivoimaging in whole organisms, we recently introduced second harmonic generating (SHG) nanoprobes. Here we present a protocol for the preparation and use of a particular SHG nanoprobe label, barium titanate (BT), for in vivoimaging in living zebrafish embryos. Chemical treatment of the BT nanoparticles results in surface coating with amine-terminal groups, which act as a platform for a variety of chemical modifications for biological applications. Here we describe cross-linking of BT to a biotin-linked moiety using click chemistry methods and coating of BT with nonreactive poly(ethylene glycol) (PEG). We also provide details for injecting PEG-coated SHG nanoprobes into zygote-stage zebrafish embryos, and in vivoimaging of SHG nanoprobes during gastrulation and segmentation. Implementing the PROCEDURErequires a basic understanding of laser-scanning microscopy, experience with handling zebrafish embryos and chemistry laboratory experience. Functionalization of the SHG nanoprobes takes ∼3 d, whereas zebrafish preparation, injection and imaging setup should take approximately 2–4 h.

A brief review of the statistics, wOunding mechanisms, and immediate treatment of combat casualties as seen in the recent conflict in Vietnam is presented, along with the avenues available to the surgeon in the long-term reconstruction of such casualties.

The benefits of quantifying or modeling inventory problems have been well recognized in business management. Many retail businesses, including a substantial portion of small retailers, handle seasonal or style goods. However, in the retailing, marketing and small business management literature there is little or no discussion of models for handling seasonal-style goods inventory management problems. The purpose of this article is to present a basic model which has been developed in the management science/operations research literature.

The perceptions of priority service needs of public agency personnel and a sample population of elderly urban poor are identified and compared. A Delphi research tool used to poll agency experts is reviewed. Data indicate that the consensus of opinion from the agency panel differed markedly from responses of the elderly sample. Policy implications of these differences are discussed.

Seven patients with deep second- and third-degree burns covering 15%, 31%, 34%, 40%, 47%, 51%, and 60% of their bodies were treated with large doses of heparin sodium administered parenterally and topically. Heparin relieved the pain and prevented burn extension so that the initial burn size was the maximum eventual size. No edema, symptoms of toxic reactions, or shock developed. Compared to Brooks' formula or Evans' formula, fluid therapy requirements were significantly less (P <.001). No escharotomy or fasciectomy was required during heparin treatment; one fasciectomy was done later. There was enhanced revascularization, granulation, and re-epithelialization without contracture, infection, or graft. No bleeding problems occurred. No respiratory problems occurred during treatment. One case of pneumonitis occurred later. One death from gram-negative septicemia occurred 35 days after heparin therapy was terminated. The effect of heparin was dose-related and dose-dependent.

Several letters to the editor are presented in response to articles in previous issues including "Navy lawyers defend rejection of atheist chaplain" in the June 18, 2015 issue, "Should the military ban Rebel flag?" in the June 24 issue and "Navy celebrates once-secret sub now on display in museum."