Appropriate Regulation of Antibiotics in Livestock Feed

For decades, antibiotics have been widely used, saving lives and reducing suffering. Such drugs are routinely employed among both human and farm animal populations. However, scientific data now links the use of antibiotics at subtherapeutic levels in livestock feed to the spread of antibiotic resistant bacteria in the human population. After examining the current research, this Article concludes that despite short-term economic benefits associated with the widespread use of antibiotics in agriculture, the risk to human health justifies a change in policy. This Article recommends a number of steps to minimize the spread of antibiotic resistance. The primary changes would be to phase out the use of antibiotics as livestock feed additives, and to refuse to approve new drugs for this purpose. In either instance, this use would be permissible if the drug sponsor provides convincing evidence that the agricultural use of its particular antibiotic presents no appreciable risk to human health

Bismuth-Based Nano- and Microparticles in X-Ray Contrast, Radiation Therapy, and Radiation Shielding Applications

Bismuth has gained attention in preclinical research because of its ability to attenuate X-rays and high biocompatibility, which make it an excellent element for use in a biomedical agent or in radiation shielding. Developments in the synthesis of elemental bismuth nano- and microparticles, their X-radiation interactions, and their biological interactions will be reviewed in this chapter. The chapter will pay special focus to emerging medical applications of elemental bismuth nano- and microparticles, including the possibility of targeted molecular X-ray imaging, photo-thermal and X-radiation dose enhancing therapies for cancer treatment, and the construction of flexible radiation shielding materials and X-ray opaque devices

Determinants of Obesity: Racial Differences

BACKGROUND: Obesity is a major public health problem. Studies have shown that there are racial and ethnic differences in the prevalence of obesity. However, there is limited research that examines the effects of sedentary and poor lifestyle behaviors and obesity among different racial and ethnic groups. Furthermore, most studies focus on the problem of obesity among children. This study was conducted to examine racial differences in determinants of obesity in adults in the United States. METHODS: Data from the 2005 Behavioral Risk Factor Surveillance System was used for this analysis. Demographics, lifestyle behaviors, and existence of chronic diseases were assessed. Data was stratified by race and multiple logistic regression analysis was conducted to examine determinants of obesity by race. RESULTS: The majority of the study participants (59%) were overweight or obese (BMI 22500). The following determinants were found to have a significant association with risk of obesity in whites, blacks and Hispanics: age, marital status, consumption of dietary recommendations of hits and vegetables, smoking status, and alcohol consumption. For whites, education and income level did not show a statistically significant association with obesity. For African Americans, sex, physical activity, and income levels did not have statistically significant associations with obesity. Income did show a statistically significant association with obesity in Hispanics.CONCLUSION: Overall, it was found that the determinants of obesity vary with ethnic groups. In order to effectively combat obesity, smoking cessation must also be paired with a healthy diet and regular exercise. In addition, interventions must be made in correlation with the needs of the community

Venus/Mercury swingby with Venus capsule. Preliminary science objectives and experiments for use in advanced mission studies

Venus/Mercury swingby with Venus capsule - preliminary science objectives and experiments for use in advanced mission studie

Functional interaction of chloroplast SRP/FtsY with the ALB3 translocase in thylakoids: substrate not required

Integration of thylakoid proteins by the chloroplast signal recognition particle (cpSRP) posttranslational transport pathway requires the cpSRP, an SRP receptor homologue (cpFtsY), and the membrane protein ALB3. Similarly, Escherichia coli uses an SRP and FtsY to cotranslationally target membrane proteins to the SecYEG translocase, which contains an ALB3 homologue, YidC. In neither system are the interactions between soluble and membrane components well understood. We show that complexes containing cpSRP, cpFtsY, and ALB3 can be precipitated using affinity tags on cpSRP or cpFtsY. Stabilization of this complex with GMP-PNP specifically blocks subsequent integration of substrate (light harvesting chl a/b-binding protein [LHCP]), indicating that the complex occupies functional ALB3 translocation sites. Surprisingly, neither substrate nor cpSRP43, a component of cpSRP, was necessary to form a complex with ALB3. Complexes also contained cpSecY, but its removal did not inhibit ALB3 function. Furthermore, antibody bound to ALB3 prevented ALB3 association with cpSRP and cpFtsY and inhibited LHCP integration suggesting that a complex containing cpSRP, cpFtsY, and ALB3 must form for proper LHCP integration

Aerobic Method for the Synthesis of Nearly Size-Monodisperse Bismuth Nanoparticles from a Redox Non-Innocent Precursor

Herein, we report an aerobic synthesis method to produce bismuth nanoparticles (Bi NPs) with average diameters in the range 40-80 nm using commercially available bismuth triiodide (BiI3) as starting material; the method uses only readily available chemicals and conventional laboratory equipment. Furthermore, size data from replicates of the synthesis under standard reaction conditions indicate that this method is highly reproducible in achieving Bi NP populations with low standard deviations in the mean diameters. We also investigated the mechanism of the reaction, which we determined results from the reduction of a soluble alkylammonium iodobismuthate precursor species formed in situ. Under appropriate concentration conditions of iodobismuthate anion, we demonstrate that burst nucleation of Bi NPs results from reduction of Bi3+ by the coordinated, redox non-innocent iodide ligands when a threshold temperature is exceeded. Finally, we demonstrate phase transfer and silica coating of the Bi NPs, which results in stable aqueous colloids with retention of size, morphology, and colloidal stability. The resultant, high atomic number, hydrophilic Bi NPs prepared using this synthesis method have potential for application in emerging X-ray contrast and X-ray therapeutic applications

The Effects of Suspended Sediment on Japanese Medaka (Oryzias latipes) and Mosquitofish (Gambusia affinis) Metabolism

Sedimentation is recognized as a significant environmental stressor in aquatic ecosystems and high amounts of suspended sediments (SS) in streams are known to negatively affect aquatic organisms. In particular, it has been hypothesized that many fish species mayexhibit increased respiration rates when exposed to elevated SS. To evaluate this hypothesis, we evaluated the acute response (3 hour exposure) of two small, freshwater fish species exposed to high suspended sediment loads using experimental respirometry chambers which measure oxygen consumption as a proxy of metabolism. Our results indicate that Japanese Medaka (Oryzias latipes) did not exhibit a significantly greater oxygen consumption, as compared to control fish, when exposed to chamber sediment of 0.17 g/L (p-value of 0.41), though oxygen consumption was higher for sediment treatments. However, mosquitofish (Gambusia affinis) exposed to 0.17 g/L did exhibit noticeably greater oxygen consumption compared to fish in no-sediment control test, but not at statistically significant levels (p-value of 0.07). Further study is needed with increased sample sizes and across SS levels to determine the threshold of increased metabolic rate among freshwater species exposed to SS

The Need for School-Based Teen Dating Violence Prevention

Schools have several competing demands, and often suffer from inefficient access to needed resources. Thus, the addition of any program into an already overtaxed school system must be met with convincing evidence that 1) a need or problem exists and is relevant to the education of students, 2) the problem is amenable to change, and 3) addressing the problem is in the best interest of educators and students. The purpose of the present paper is to present a case for inclusion of teen dating violence prevention programs in middle and high schools. We also discuss a recent survey of 219 employees of a suburban school district in southeast Texas. Specifically, we examined their perceived need for and appropriateness of a school-based dating violence prevention program. The anonymous internet-based survey revealed that a majority of participants believed that teen dating violence was a problem, 19% reported having observed an instance of teen dating violence, and 82% believed school to be an appropriate outlet for the implementation of a dating violence prevention program

Avionics Architectures for Exploration: Building a Better Approach for (Human) Spaceflight Avionics

The field of Avionics is advancing far more rapidly in terrestrial applications than in space flight applications. Spaceflight Avionics are not keeping pace with expectations set by terrestrial experience, nor are they keeping pace with the need for increasingly complex automation and crew interfaces as we move beyond Low Earth Orbit. NASA must take advantage of the strides being made by both space-related and terrestrial industries to drive our development and sustaining costs down. This paper describes ongoing efforts by the Avionics Architectures for Exploration (AAE) project chartered by NASA's Advanced Exploration Systems (AES) Program to evaluate new avionic architectures and technologies, provide objective comparisons of them, and mature selected technologies for flight and for use by other AES projects. Results from the AAE project's FY13 efforts are discussed, along with the status of FY14 efforts and future plans

Avionics Architectures for Exploration: Ongoing Efforts in Human Spaceflight

The field of Avionics is advancing far more rapidly in terrestrial applications than in spaceflight applications. Spaceflight Avionics are not keeping pace with expectations set by terrestrial experience, nor are they keeping pace with the need for increasingly complex automation and crew interfaces as we move beyond Low Earth Orbit. NASA must take advantage of the strides being made by both space-related and terrestrial industries to drive our development and sustaining costs down. This paper describes ongoing efforts by the Avionics Architectures for Exploration (AAE) project chartered by NASA's Advanced Exploration Systems (AES) Program to evaluate new avionic architectures and technologies, provide objective comparisons of them, and mature selected technologies for flight and for use by other AES projects. The AAE project team includes members from most NASA centers, and from industry. It is our intent to develop a common core avionic system that has standard capabilities and interfaces, and contains the basic elements and functionality needed for any spacecraft. This common core will be scalable and tailored to specific missions. It will incorporate hardware and software from multiple vendors, and be upgradeable in order to infuse incremental capabilities and new technologies. It will maximize the use of reconfigurable open source software (e.g., Goddard Space Flight Center's (GSFC's) Core Flight Software (CFS)). Our long-term focus is on improving functionality, reliability, and autonomy, while reducing size, weight, and power. Where possible, we will leverage terrestrial commercial capabilities to drive down development and sustaining costs. We will select promising technologies for evaluation, compare them in an objective manner, and mature them to be available for future programs. The remainder of this paper describes our approach, technical areas of emphasis, integrated test experience and results as of mid-2014, and future plans. As a part of the AES Program, we are encouraged to set aggressive goals and fall short if necessary, rather than to set our sights too low. We are also asked to emphasize providing our personnel with hands-on experience in development, integration, and testing. That we have embraced both of these philosophies will be evident in the descriptions below