Consensus guidelines for the use and interpretation of angiogenesis assays

The formation of new blood vessels, or angiogenesis, is a complex process that plays important roles in growth and development, tissue and organ regeneration, as well as numerous pathological conditions. Angiogenesis undergoes multiple discrete steps that can be individually evaluated and quantified by a large number of bioassays. These independent assessments hold advantages but also have limitations. This article describes in vivo, ex vivo, and in vitro bioassays that are available for the evaluation of angiogenesis and highlights critical aspects that are relevant for their execution and proper interpretation. As such, this collaborative work is the first edition of consensus guidelines on angiogenesis bioassays to serve for current and future reference

Combined Forward-Backward Asymmetry Measurements in Top-Antitop Quark Production at the Tevatron

The CDF and D0 experiments at the Fermilab Tevatron have measured the asymmetry between yields of forward- and backward-produced top and antitop quarks based on their rapidity difference and the asymmetry between their decay leptons. These measurements use the full data sets collected in proton-antiproton collisions at a center-of-mass energy of $\sqrt s =1.96$ TeV. We report the results of combinations of the inclusive asymmetries and their differential dependencies on relevant kinematic quantities. The combined inclusive asymmetry is $A_{\mathrm{FB}}^{t\bar{t}} = 0.128 \pm 0.025$. The combined inclusive and differential asymmetries are consistent with recent standard model predictions

Using high throughput technology to characterize disease response in hexaploid wheat

Wheat (Triticum aestivum L.) is vital for human consumption, global economics as well as societal structure. Wheat is found in a wide range of food products as well as forage for livestock. Yield loss in any crop cannot only affect the world food supply, but also economic stability. Plant viruses and pathogens can greatly impact plant health and yield. The Barley- and Cereal yellow dwarf viruses (BYDV and CYDV, respectively), can cause dramatic yield loss, upwards of 50% in some areas. The yellow dwarf viruses (YDVs) have a wide host range and are spread by aphid transmission. YDVs move up the mouth parts of the aphid and into the hindgut. Aphids feeding on the plant phloem with their stylet, deposit the virus. In wheat, there is little natural resistance to a YDV multi-infection. In recent years, an introgression into wheat with a segment of wheatgrass (Thinopyrum intermedium) 7E2 chromosome confers resistance to all YDVs. While the wheatgrass chromosome segment introgression has been mapped to the long arm of 7D, few polymorphic markers have been developed to determine the exact location of the wheatgrass chromosome segment, and thus, YDV resistance. Also, the mode of resistance the wheatgrass introgression has introduced is not well understood. It has been demonstrated in YDV resistant wheat-wheatgrass lines that YDVs are unable to move into the phloem and spread systemically. In other species, both mammalian and plant, it has been demonstrated that small RNAs (sRNAs) are involved in disease response. Likewise, mammalian and plant viruses have developed a set of proteins, called viral suppressors, that counteract the host\u27s response. CYDVs posses such a viral suppressor called P0, which recently has been shown to affect sRNA response machinery. In this thesis, a high throughput approach was taken to examine disease response to YDVs in a YDV resistant wheat-wheatgrass introgression line in two ways: 1.) identify more polymorphic markers to the 7E2 wheatgrass region of the wheat-wheatgrass introgression line, and 2.) identify sRNAs expressed during YDV infection of a YDV resistant wheat-wheatgrass introgression line. To identify polymorphic markers to the wheatgrass region of the wheat-wheatgrass introgression lines, wheat oligonucleotide microarray technology (Affymetrix) was used. Robustified project pursuit (RPP) identified SFPs (single feature polymorphism) candidates by comparing microarray hybridization intensities between the wheat line, Chinese Spring, and the wheat-wheatgrass substitution lines. One hundred fragments were cloned and sequenced and 4 markers were bin mapped to the group 7 wheat chromosomes using Chinese spring deletion lines. Markers specific for the wheatgrass 7E2 chromosome were not identified using the wheat oligonucleotide array because comparison of genotypes would only identify SFPs on the wheat chromosomes. The second part of the thesis was a high throughput examination of sRNA in a YDV resistant wheat-wheatgrass introgression line. A time course study was conducted using three different treatments 1. aphids containing the CYDV-RPV isolate (viruliferous aphids), 2. aphids without any virus (non-viruliferous aphids), and 3. no aphids. Each treatment had three biological replicates. Total RNA was isolated, fractionated, and sRNA libraries were made using the small RNA expression kit (SREK) (Applied Biosystems™) for SOLiD™ (Applied Biosystems™) sequencing. Computational methods developed for wheat SOLiD™ (Applied Biosystems™) sequencing data were developed and identified 5000 unique putative sRNAs in a YDV resistant wheat-wheatgrass introgression line. Of the 5000 unique putative sRNAs, 70 were determined computationally to be conserved microRNAs (miRNAs) and small interfering RNAs (siRNAs) in other plant species. Also, among sRNA between 17 and 28 nucleotides (nts) in length, 76% of the data was 17 nts. Biological validation by time course Northern blotting of 8 putative conserved sRNAs and 4 short (17-18 nt) sRNAs showed no difference in sRNA expression. However, tissue-specific (tissue included root, stem, leaf, spikelet, and flag leaf) Northern blots showed difference in expression of the 12 putative conserved sRNAs. No CYDV-RPV specific viral sRNA (vsRNA) were identified in this data set. However, over 5000 unique sRNAs have yet to be validated. Future directions of this project would be to examine additional unique sRNAs in this data set as well as sRNA expression in a YDV susceptible wheat-wheatgrass introgression line

Structure-property relationships for a series of poly(ester amide)s containing amino acids

Poly(ester amide)s (PEAs) composed of variable diols, dicarboxylic acids, and α-amino acids were synthesized and characterized to elucidate structure-property relationships. The PEAs were synthesized using both solution and interfacial approaches to obtain varying molecular weights (MWs) and polydispersities. Studies using differential scanning calorimetry and powder X-ray diffraction revealed a range of amorphous and semicrystalline behavior that was dependent on structure. The viscosities of the PEAs as a function of temperature were studied by rheology, and phase transitions were confirmed for some polymers. Mechanical properties were also investigated, and it was found that the PEAs could be tuned to exhibit elastomeric or brittle behavior by varying both the length of the diol and the amino acid moiety. This information provides new insights into the effects of PEA structure, MW, and MW distribution on PEA properties and will aid in the design and selection of PEAs with optimal properties for targeted applications. © 2013 American Chemical Society

Measuring progress in reducing maternal mortality.

The need to monitor progress in reducing maternal mortality has a long history, which can be traced back to the 1700s in some parts of the Western world. Today, however, this need is felt most acutely in developing countries, where the priority is to stimulate, evaluate and sustain action to prevent these essentially avoidable deaths. Over the last two decades, considerable efforts have been made to understand and overcome the measurement challenges of maternal mortality in the context of weak information systems, and new and enhanced methods and tools have emerged