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Abstract Background Resistance and susceptibility to scrapie has been associated with single nucleotide polymorphisms located within codons 136, 154 and 171 of the ovine prion protein gene (PRNP). Dual-labelled HyBeacon probes were developed to analyse single and clustered polymorphisms within these and neighbouring codons. Methods Extracted DNAs and unpurified blood samples were genotyped with respect to polymorphisms in PRNP codons 136, 141, 154 and 171. PCR amplicons were investigated using a LightTyper instrument, measuring the stability of probe/target hybridisation through peak melting temperatures and determining the sequence of nucleotides at polymorphic sites. Results The performance of HyBeacon assays was evaluated in a validation study comparing genotypes with those obtained using a primer extension assay (Sequenom MassEXTEND) analysed on a MALDI-ToF mass spectrometer. Over 12,000 sheep samples were successfully genotyped, reliably detecting A136, V136, T136, T137, L141, F141 R154, H154, L168, R171, Q171, H171 and K171 sequence variants using only 4 HyBeacon probes. Conclusion HyBeacon assays provide an extremely robust and accurate method for the analysis of single and clustered PRNP polymorphisms in a high-throughput format. The flexibility of the diagnostic tests ensures that samples are correctly genotyped even in the presence of additional sequence variations that flank the polymorphisms of interest. Such sequence variations may also be neutralised using universal bases such as 5-nitroindole if required.

Westudy the films formed by tetradecylamine (TDA) at the water–dodecaneinterface in the presence of hydrogen phosphate ions. Using Fouriertransform infrared spectroscopy (FTIR), interfacial shear rheology,confocal fluorescence microscopy, cryo-scanning electron microscopy(cryo-SEM), and small-angle neutron scattering (SANS), we find thatbetween pH 5 and 8 tetradecylammonium cations bind to hydrogen phosphateanions to form needle-shaped crystallites of tetradecylammonium hydrogenphosphate (TAHP). These crystallites self-assemble into films witha range of morphologies; below pH 7, they form brittle, continuoussheets, and at pH 8, they form lace-like networks that deform plasticallyunder shear. They are also temperature-responsive: when the systemis heated, the film thins and its rheological moduli drop. We findthat the temperature response is caused by dissolution of the filmin to the bulk fluid phases. Finally, we show that these films canbe used to stabilize temperature-responsive water-in-oil emulsionswith potential applications in controlled release of active molecules. [ABSTRACT FROM AUTHOR]

The article discusses the role of technological innovations in the energy industry amidst the competitive world marketplace. It mentions that technological innovations are always challenge by several factors including competitive pressures from market forces and the capitalist side of the free market economy. It discusses the significance of technological innovations among the farmers in Canada and on their economic advantage.

Background: Resistance and susceptibility to scrapie has been associated with single nucleotide polymorphisms located within codons 136, 154 and 171 of the ovine prion protein gene (PRNP). Dual-labelled HyBeacon probes were developed to analyse single and clustered polymorphisms within these and neighbouring codons. Methods: Extracted DNAs and unpurified blood samples were genotyped with respect to polymorphisms in PRNP codons 136, 141, 154 and 171. PCR amplicons were investigated using a LightTyper instrument, measuring the stability of probe/target hybridisation through peak melting temperatures and determining the sequence of nucleotides at polymorphic sites. Results: The performance of HyBeacon assays was evaluated in a validation study comparing genotypes with those obtained using a primer extension assay (Sequenom MassEXTEND) analysed on a MALDI-ToF mass spectrometer. Over 12,000 sheep samples were successfully genotyped, reliably detecting A136, V13, T136, T137, L141, F141 R154, H154, L168, R171, Q171, H171 and K171 sequence variants using only 4 HyBeacon probes. Conclusion: HyBeacon assays provide an extremely robust and accurate method for the analysis of single and clustered PRNP polymorphisms in a high-throughput format. The flexibility of the diagnostic tests ensures that samples are correctly genotyped even in the presence of additional sequence variations that flank the polymorphisms of interest. Such sequence variations may also be neutralised using universal bases such as 5-nitroindole if required. [ABSTRACT FROM AUTHOR]

The article discusses vector operations and mathematical proofs using vectors and trigonometry. The proofs follow the basic properties of vectors, operations with vectors and dot product. The dot product is used to prove the law of cosines, while vectors are used to show that a semicircle's inscribed angle is a right angle. An excellent application of trigonometry, triangle manipulations and vectors can be learned from the proof of law of cosines.

HyBeacon probes are single-stranded oligonucleotides with one or more internal base(s) labeled with a fluorescent dye. When a probe forms a duplex with its target sequence, the level of fluorescence emission increases considerably. HyBeacons have been developed as new tools for rapid sequence detection and discrimination and have been employed in a wide variety of applications including infectious diagnostics and analysis of human polymorphisms. Single-labeled (FVG1) and dual-labeled (FVG11) probes were designed to analyze the factor V Leiden (R506Q) polymorphism which causes an increased risk of deep vein thrombosis and pulmonary embolism. Detection and identification of factor V alleles is performed by melting curve analysis and determination of probe melting temperature (T(m)). HyBeacon hybridization to the glutamine allele (Q) causes the formation of mismatched DNA duplexes that are detected through decreases in T(m). HyBeacon probes are included in homogeneous PCR assays to genotype samples with respect to the factor V polymorphism within 20 min, using purified DNAs and unpurified saliva/blood samples. This paper describes the preparation of homogeneous PCR assays, LightCycler target amplification, and subsequent melting curve analysis. This chapter also describes the use of homologous oligonucleotides and melting curve analysis as a method for probe evaluation.