Year-to-year changes of vertical temperature distribution in the California Current region: 1954 to 1986

Studies by Enfield and Allen (1980), McLain et al (1985), and others have shown that anomalously warm years in the northern coastal California Current correspond to El Niño conditions in the equatorial Pacific Ocean. Ocean model studies suggest a mechanical link between the northern coastal California Current and the equatorial ocean through long waves that propagate cyclonically along the ocean boundary (McCreary 1976; Clarke 1983; Shriver et al 1991). However, distinct observational evidence of such an oceanic connection is not extensive. Much of the supposed El Niño variation in temperature and sea level data from the coastal California Current region can be associated with the effects of anomalously intense north Pacific atmospheric cyclogenesis, which is frequently augmented during El Niño years (Wallace and Gutzler 1981; Simpson 1983; Emery and Hamilton 1984). This study uses time series of ocean temperature data to distinguish between locally forced effects, initiated by north Pacific atmospheric changes, and remotely forced effects, initiated by equatorial Pacific atmospheric changes related to El Niño events.

Cloning of bradykinin precursor cDNAs from skin of Bombina maxima reveals novel bombinakinin M antagonists and a bradykinin potential peptide

Bombinakinin M (DLPKINRKGP-bradykinin) is a bradykinin-related peptide purified from skin secretions of the frog Bombina maxima. As previously reported, its biosynthesis is characterized by a tandem repeats with various copy numbers of the peptide and sometimes co-expressed with other structure-function distinguishable peptides. At present study, two novel cDNAs encoding bombinakinin M and its variants were cloned from a cDNA library from the skin of the frog. The encoded two precursor proteins are common in that each contains three repeats of a novel 16-amino acid peptide unit and one copy of kinestatin at their N- and C-terminal parts, respectively. They differ in that the first precursor contains two copies of bombinakinin M and the second one contains one copy of a novel bombinakinin M variant. Bombinakinin M was found to elicit concentration-dependent contractile effects on guinea pig ileum, with an EC50 value of 4 nM that is four times higher than that of bradykinin (1 nM). Interestingly, the synthetic peptide (DYTIRTRLH-amide), as deduced from the 16-amino acid peptide repeats in the newly cloned cDNAs, possessed weak inhibitory activity on the contractile effects of bombinakinin M, but not on that of bradykinin. Furthermore, the newly identified bombinakinin M variant (DLSKMSFLHG-Ile(1)-bradykinin), did not show contractile activity on guinea pig ileum, but showed potentiation effect on the myotropic activity of bradykinin. In a molar raito of 1:58, it augmented the activity of bradykinin up to two-fold. (C) 2004 Elsevier B.V. All rights reserved.

Surface excavation with model predictive control

This paper describes the application of variable-horizon model predictive control to trajectory generation in surface excavation. A nonlinear dynamic model of a surface mining machine digging in oil sand is developed as a test platform. This model is then stabilised with an inner-loop controller before being linearised to generate a prediction model. The linear model is used to design a predictive controller for trajectory generation. A variable horizon formulation is augmented with extra terms in the cost function to allow more control over digging, whilst still preserving the guarantee of finite-time completion. Simulations show the generation of realistic trajectories, motivating new applications of variable horizon MPC for autonomy that go beyond the realm of vehicle path planning. ©2010 IEEE.

Unity in diversity: electronic patient record use in multidisciplinary practice

In this paper we examine the use of electronic patient records (EPR) by clinical specialists in their development of multidisciplinary care for diagnosis and treatment of breast cancer. We develop a practice theory lens to investigate EPR use across multidisciplinary team practice. Our findings suggest that there are oppositional tendencies towards diversity in EPR use and unity which emerges across multidisciplinary work, and this influences the outcomes of EPR use. The value of this perspective is illustrated through the analysis of a year-long, longitudinal case study of a multidisciplinary team of surgeons, oncologists, pathologists, radiologists, and nurse specialists adopting a new EPR. Each group adapted their use of the EPR to their diverse specialist practices, but they nonetheless orientated their use of the EPR to each others' practices sufficiently to support unity in multidisciplinary teamwork. Multidisciplinary practice elements were also reconfigured in an episode of explicit negotiations, resulting in significant changes in EPR use within team meetings. Our study contributes to the growing literature that questions the feasibility and necessity of achieving high levels of standardized, uniform health information technology use in healthcare.

The need for a trawl fishery on Lake Victoria

The idea of mechanised fishing on Lake Victoria is not new. Trawling experiments have been carried out in the past by the East African Freshwater Fisheries Research Organisation (EAFFRO), the Lake Victoria Fisheries Service and the Uganda Fisheries Department. In 1950 it was recognised by EAFFRO that commercial possibilities existed in the exploitation of Haplochromis by this gear. However, it was not until 1966 that, by a happy collaboration of the Uganda Fisheries Department and EAFFRO, the vessel 'Darter' was converted into a stern trawler and serious and successful experimentation into trawl fishing commenced. Darter has continued to undertake trawling work ever since and this work was augmented by the arrival in 1967 of the Lake Victoria Fisheries Research Project's vessel 'Ibis'.

Closing the gap: Improved bounds on optimal POMDP solutions

POMDP algorithms have made significant progress in recent years by allowing practitioners to find good solutions to increasingly large problems. Most approaches (including point-based and policy iteration techniques) operate by refining a lower bound of the optimal value function. Several approaches (e.g., HSVI2, SARSOP, grid-based approaches and online forward search) also refine an upper bound. However, approximating the optimal value function by an upper bound is computationally expensive and therefore tightness is often sacrificed to improve efficiency (e.g., sawtooth approximation). In this paper, we describe a new approach to efficiently compute tighter bounds by i) conducting a prioritized breadth first search over the reachable beliefs, ii) propagating upper bound improvements with an augmented POMDP and iii) using exact linear programming (instead of the sawtooth approximation) for upper bound interpolation. As a result, we can represent the bounds more compactly and significantly reduce the gap between upper and lower bounds on several benchmark problems. Copyright © 2011, Association for the Advancement of Artificial Intelligence. All rights reserved.

Hydrothermally-grown ZnO nanowire tips for scanning tunnelling microscopy.

The probe tip is pivotal in determining the resolution and nature of features observed in the Scanning Tunnelling Microscope (STM). We have augmented a conventional Pt/Ir metallic tip with a hydrothermally grown ZnO nanowire (NW). Atomic resolution imaging of graphite is attained. Current-voltage (IV) characteristics demonstrate an asymmetry stemming from the unintentional n-type doping of the ZnO NW, whereas the expected Schottky barrier at the ZnO-Pt/Ir interface is shown to have negligible effect. Moreover the photoconductivity of the system is investigated, paving the way towards a photodetector capable of atomic resolution.