Abstract: An artificial toolface reference system includes a power supply providing current to a ground lead and a reference lead. A ground point is coupled to the ground lead and in electrical connection with the ground. A reference wellbore includes a reference conductor in electrical connection with the ground. The reference conductor is in electrical connection with the reference lead. A guidance sensor positioned outside the reference wellbore includes at least one magnetometer. The power supply may be used to provide a current through the reference conductor, the ground, and the ground point such that a reference magnetic field is generated along the reference conductor. The guidance sensor may measure the reference magnetic field with a magnetometer. An artificial magnetic toolface may be calculated therefrom.

Abstract: An artificial toolface reference system includes a power supply providing current to a ground lead and a reference lead. A ground point is coupled to the ground lead and in electrical connection with the ground. A reference wellbore includes a reference conductor in electrical connection with the ground. The reference conductor is in electrical connection with the reference lead. A guidance sensor positioned outside the reference wellbore includes at least one magnetometer. The power supply may be used to provide a current through the reference conductor, the ground, and the ground point such that a reference magnetic field is generated along the reference conductor. The guidance sensor may measure the reference magnetic field with a magnetometer. An artificial magnetic toolface may be calculated therefrom.

Abstract: The present invention provides a method of using a physiologically-based pharmacokinetic model to select a prodrug molecule (NO—X) comprising a therapeutic agent X (e.g. nonsteroidal anti-inflammatory drug, (NSAID)) and an appropriate nitric oxide donor NO. The NSAID can be a non-selective or selective cyclooxygenase inhibitor or other biocompatible compound comprising a carboxyl group. The pharmacokinetic model uses in vitro and/or in silico data to estimate an optimal set of parameters that can predict whether a particular NO—X candidate is capable of producing desirable therapeutic effects, e.g. enhanced anti-inflammatory activity, reduced intestinal, cardiac and renal toxicity. Accordingly, the present invention can greatly enhance proper selection of an appropriate candidate for drug development, thereby minimizing development time and conserving costs.