Food and Drug Administration Regulation of Food Safety

Food-borne illness remains a major public health challenge in the United States, causing an estimated 48 million illness episodes and 3000 deaths annually. The FDA Food Safety Modernization Act (FSMA), enacted in 2011, gives the Food and Drug Administration (FDA) new tools to regulate food safety. The act emphasizes prevention, enhanced recall authority, and oversight of imported food. The FSMA brings the FDA’s food safety regulation in line with core tenets of public health by focusing on preventing outbreaks, rather than reacting to them, and differentiating between foods and food producers based on the degree of risk they pose. The FSMA also recognizes the increasing importance of imported food and enhances the ability of the FDA to safeguard the U.S. food supply from hazards originating abroad. The act achieves its prevention objectives through requiring food production facilities to establish preventive control plans and by increasing inspection frequency—a shortcoming of the FDA in recent years. The act also enhances the FDA’s ability to respond to food safety problems when they occur. Through pilot projects on food tracing systems and an enhanced surveillance system, the FDA will be have better tools to determine the source of outbreaks. Additionally, the act gives the FDA new mandatory recall authority—a badly needed addition to its enforcement capabilities. In an increasingly globalized food environment, the FSMA gives the FDA new authority to regulate imported food. Among other provisions, the act allows FDA to inspect foreign facilities and to partner with foreign food regulatory agencies to help build capacity. Through new tools and increased enforcement, the FSMA holds great promise for public health. The act, however, leaves several regulatory gaps, including keeping the food safety functions of the USDA and FDA separate. Additionally, the potential of the act to improve food safety may be thwarted by inadequate funding in the current budget environment. The act includes numerous programs for building the capacity of domestic and foreign regulators and food producers. Such programs are essential to an improved food safety system, but require adequate funding from Congress to be fully implemented. In addition to national capacity building, FDA and Congress should fully engage partners in government and industry to improve global food safety at the international level

Methods for predicting thermal stress cracking in turbine stator or rotor blades Summary report

Test rig for predicting thermal stress cracking in turbine stator or rotor blade

Catalytic surface effects on contaminated space shuttle tile in a dissociated nitrogen stream

Visual inspection revealed contamination on the surface of tiles removed from the lower section of the space shuttle orbiter after the second flight of Columbia (STS-2). Possible sources of this contamination and the effect on surface catalycity are presented

Characterization of lunar surface materials for use in construction

The Workshop on the Concept of a Common Lunar Lander, which was held at the NASA Johnson Space Center on July 1 and 2, 1991, discussed potential payloads to be placed on the Moon by a common, generic, unmanned, vehicle beginning late in this decade. At this workshop, a variety of payloads were identified including a class of one-meter (and larger) optical telescopes to operate on the lunar surface. These telescopes for lunar-based astronomy are presented in an earlier section of this report. The purpose of this section is to suggest that these and other payloads for the Common Lunar Lander be used to facilitate technology development for the proposed 16-meter Aperture UV/Visible/IR Large Lunar Telescope (LLT) and a large optical aperture-synthesis instrument analogous to the Very Large Array of the National Radio Astronomy Observatory

Performance of an ablator for Space Shuttle inorbit repair in an arc-plasma airstream

An ablator patch material performed well in an arc plasma environment simulating nominal Earth entry conditions for the Space Shuttle. Ablation tests using vacuum molded cones provided data to optimize the formulation of a two part polymer system for application under space conditions. The blunt cones were made using a Teflon mold and a state of the art caulking gun. Char stability of formulations with various amounts of catalyst and diluent were investigated. The char was found to be unstable in formulations with low amounts of catalyst and high amounts of diluent. The best polymer system determined by these tests was evaluated using a half tile patch in a multiple High Temperature Reusable surface Insulation tile model. It was demonstrated that this ablator could be applied in a space environment using a state of the art caulking gun, would maintain the outer mold line of the thermal protection system during entry, and would keep the bond line temperature at the aluminum tile interface below the design limit

Development of sprayed ceramic seal systems for turbine gas path sealing

A ceramic seal system is reported that employs plasma-sprayed graded metal/ceramic yttria stabilized zirconium oxide (YSZ). The performance characteristics of several YSZ configurations were determined through rig testing for thermal shock resistance, abradability, and erosion resistance. Results indicate that this type of sealing system offers the potential to meet operating requirements of future gas turbine engines

Carbohydrates as chiral templates

1987 Spring.Includes bibliographical references.Carbohydrates can serve as a source of functionalized asymmetric carbon atoms. The synthesis of a carbon fragment derived from 2-deoxy-glucose is described as an optically pure intermediate (34) for the synthesis of the antibiotic thienamycin. Natural products containing sugar moieties are direct targets for synthetic strategems utilizing carbohydrate precursors. The synthesis of naturally occurring C-glycosides from readily available sugars require carbon bond formation at the acetal carbon. Reported, herein, is methodology for the conversion of hemiacetals to the corresponding 2'-thiopyridyl acetals and subsequent metal activation toward nucleophilic displacement by carbon species resulting in efficient C-glycosidation. A glucosyl substrate (122) and two ribosyl substrates (147, 154) are described and their stereoselective reactions with different carbon nucleophiles are examined. The glucose substrate (122) shows general α-selectivity in carbon-carbon bond formation. The selectivity in the ribosyl substrates is quite good but, exhibits a large dependence on the particular nucleophile. The total synthesis of (+)- showdomycin is achieved employing a β-selective coupling of trimethoxybenzene and the ribosyl thioacetal (154) utilizing silver (I) activation. Preparation of other useful C-nucleoside precursors containing the required β-stereochemistry are reported. The use of these metal activated thiopyridyl acetals for intramolecular O-glycosidations are also investigated. Approaches to the [3.1.1) bycyclic oxetane of the thromboxane A2 nucleus using this methodology are examined. The use of a polymer bound mercury(II) salt (226) for activation of the thio-residue is shown to be useful in an intramolecular O-glycosidation resulting in the 1,5 anhydro-furanose (186). This polymer bound reagent should potentially represent an advantageous heterogeneous alternative to the homogeneous metal salts; particularly for glycosidations of sensitive substrates. In general, these thiopyridyl-acetals are stable precursors that may be readily activated by thiophilic metal salts for efficient nucleophilic substitution reactions

A lunar far-side very low frequency array

Papers were presented to consider very low frequency (VLF) radio astronomical observations from the moon. In part 1, the environment in which a lunar VLF radio array would function is described. Part 2 is a review of previous and proposed low-frequency observatories. The science that could be conducted with a lunar VLF array is described in part 3. The design of a lunar VLF array and site selection criteria are considered, respectively, in parts 4 and 5. Part 6 is a proposal for precursor lunar VLF observations. Finally, part 7 is a summary and statement of conclusions, with suggestions for future science and engineering studies. The workshop concluded with a general consensus on the scientific goals and preliminary design for a lunar VLF array