Abstract: Computer-implemented systems and methods are provided for optimizing hydrocarbon recovery from subsurface formations, including subsurface formations having bottom water or edgewater. A system and method can be configured to receive data indicative of by-pass oil areas in the subsurface formation from reservoir simulation, identify flow barriers in the subsurface formation based on the by-pass oil areas identified by the reservoir simulation, and predict the lateral extension of the identified flow barriers in the subsurface formation. Infill horizontal wells can be placed at areas of the subsurface formation relative to the flow barriers such that production from a horizontal well in the subsurface formation optimizes hydrocarbon recovery.

Abstract: Computer-implemented systems and methods are provided for optimizing hydrocarbon recovery from subsurface formations, including subsurface formations having bottom water or edgewater. A system and method can be configured to receive data indicative of by-pass oil areas in the subsurface formation from reservoir simulation, identify flow barriers in the subsurface formation based on the by-pass oil areas identified by the reservoir simulation, and predict the lateral extension of the identified flow barriers in the subsurface formation. Infill horizontal wells can be placed at areas of the subsurface formation relative to the flow barriers such that production from a horizontal well in the subsurface formation optimizes hydrocarbon recovery.

Abstract: The present invention provides methods for determining the genotype of a nucleic acid at the site of a polymorphism. The methods achieve sensitivities great enough to detect the presence of any difference between the nucleic acids, even single nucleotide polymorphisms. In the methods, the nucleic acid is compared to a reference nucleic acid having a known genotype. The nucleic acids can be of any length, even less than 100 base pairs. In methods, one or more extra mismatches are introduced into the nucleic acids at or near the site of the polymorphism. The nucleic acids are contacted under conditions in which they are capable of forming a stable four-way complex that can be detected to indicate that the nucleic acids differ in genotype.

Abstract: The present invention provides methods for detecting the presence or absence of a difference between two related nucleic acid sequences. In the methods, a target nucleic acid and a reference nucleic acid are contacted under conditions in which they are capable of forming a four-way nucleic acid complex with a branch structure that is capable of migration. Under the contact conditions, if the reference nucleic acid and target nucleic acid are identical, branch migration is capable of going to completion resulting in complete strand exchange. If the reference nucleic acid and target nucleic acid are different, branch migration does not go to completion, resulting in a stable four-way complex. Detection of the stable four-way complex identifies the presence of a difference between the nucleic acids. A stable four-way complex can be detected with molecules that specifically bind such complexes, by gel electrophoresis or by specific isolation of the stable four-way complex.

Abstract: The present invention provides sensitive methods for detecting the presence or absence of a difference between related nucleic acid sequences. In one aspect of the invention, a method is provided for detecting a difference in the sequence of two nucleic acid molecules. The method includes the steps of: contacting two nucleic acids under conditions that allow the formation of a four-way complex and branch migration; contacting the four-way complex with a tracer molecule and a detection molecule under conditions in which the detection molecule is capable of binding the tracer molecule or the four-way complex; and determining binding of the tracer molecule to the detection molecule before and after exposure to the four-way complex. Competition of the four-way complex with the tracer molecule for binding to the detection molecule indicates a difference between the two nucleic acids.

Abstract: The present invention provides methods for detecting the presence or absence of a difference between two related nucleic acid sequences. In the methods, a target nucleic acid and a reference nucleic acid are contacted under conditions in which they are capable of forming a four-way nucleic acid complex with a branch structure that is capable of migration. Under the contact conditions, if the reference nucleic acid and target nucleic acid are identical, branch migration is capable of going to completion resulting in complete strand exchange. If the reference nucleic acid and target nucleic acid are different, branch migration does not go to completion, resulting in a stable four-way complex. Detection of the stable four-way complex identifies the presence of a difference between the nucleic acids. A stable four-way complex can be detected with molecules that specifically bind such complexes, by gel electrophoresis or by specific isolation of the stable four-way complex.

Abstract: The present invention provides methods for detecting the presence or absence of a difference between two related nucleic acid sequences. The methods achieve sensitivities great enough to detect the presence of any difference between the nucleic acids, even single nucleotide polymorphisms. In the methods, the nucleic acids are contacted under conditions in which they are capable of forming a stable four-way complex if the nucleic acids differ in sequence. The presence of the four way complex is determined with a detection molecule and a labeled four-stranded tracer molecule.

Abstract: The present invention provides methods for determining the genotype of a nucleic acid at the site of a polymorphism. The methods achieve sensitivities great enough to detect the presence of any difference between the nucleic acids, even single nucleotide polymorphisms. In the methods, the nucleic acid is compared to a reference nucleic acid having a known genotype. The nucleic acids can be of any length, even less than 100 base pairs. In methods, one or more extra mismatches are introduced into the nucleic acids at or near the site of the polymorphism. The nucleic acids are contacted under conditions in which they are capable of forming a stable four-way complex that can be detected to indicate that the nucleic acids differ in genotype.

Abstract: The present invention provides methods for determining the genotype of a target nucleic acid. In the methods, a target nucleic acid is contacted with a probe polynucleotide and a reference nucleic acid under conditions in which they are capable of forming a four-way nucleic acid complex with a branch structure that is capable of migration. Detection of resolution of the four-way complex under the appropriate conditions indicates the genotype of the target nucleic acid.

Abstract: The present invention provides methods for detecting the presence or absence of a difference between two related nucleic acid sequences. In the methods, a target nucleic acid and a reference nucleic acid are contacted under conditions in which they are capable of forming a four-way nucleic acid complex with a branch structure that is capable of migration. Under the contact conditions, if the reference nucleic acid and target nucleic acid are identical, branch migration is capable of going to completion resulting in complete strand exchange. If the reference nucleic acid and target nucleic acid are different, branch migration does not go to completion, resulting in a stable four-way complex. Detection of the stable four-way complex identifies the presence of a difference between the nucleic acids. A stable four-way complex can be detected with molecules that specifically bind such complexes, by gel electrophoresis or by specific isolation of the stable four-way complex.