Facultative Altitudinal Movements by Mountain White-Crowned Sparrows (Zonotrichia Leucophrys Oriantha) in the Sierra Nevada

Mountain White-crowned Sparrows (Zonotrichia leucophrys oriantha) winter in Mexico and often arrive in the vicinity of their breeding grounds in the Sierra Nevada well before nesting is possible. Arrival at Tioga Pass, California (elevation 3,030 m), usually occurs in early May, but residual winter snow and adverse weather can delay nesting for weeks. We used radiotelemetry to determine whether prebreeding Mountain White-crowned Sparrows engaged in weather-related altitudinal movements during the waiting period between the end of spring migration and onset of breeding during 1995-2001, with a range of residual winter snowpacks. Interannual variation in arrival date and onset of egg laying was 18 and 41 days, respectively. We tracked females for two years and males for all seven years. During spring snowstorms (which occurred in four years), radiomarked individuals moved to lower elevation sites, where they often remained for several days. Departing birds left Tioga Pass by early afternoon and returned early in the morning after storms. More frequent storms during tracking increased the likelihood of facultative altitudinal movements, but heavier residual winter snowpack did not. Warm days increased the likelihood of birds returning to Tioga Pass from low elevation. This study demonstrates that facultative altitudinal movement behavior can be a common feature of spring arrival biology in montane-breeding birds. Received 1 November 2002, accepted 30 June 2004.Integrative Biolog

The Framework and Measure of Effective School Visioning Strategy (MCP-FIV)

This article describes a pilot study in which a prototype instrument is presented as a first step toward a reliable and valid tool that facilitates both the establishment of a visioning strategy and evaluation of the effectiveness of visioning strategies, existing or new. A brief historical perspective precedes an examination of the actual steps that comprise a visioning strategy. Analysis of research data arising from a pilot study involving the instrument suggests that school leaders are more likely to be involved in visioning strategy than parents or students. All stakeholders generally, and parents, students, and principals specifically, are more likely to be involved in visioning processes in medium-sized schools. School leaders will be challenged to consider whether change in their schools is consistent with vision that has been inclusively and collaboratively established or if such change reflects centralized, mandated, top-down processes that are simply implemented by principals.Cet article décrit une étude pilote dans laquelle un prototype d'un instrument sert de première étape vers l'élaboration d'un outil fiable et valide pour faciliter tant la mise sur pied d'une stratégie de visualisation d'avenir que pour évaluer l'efficacité de telles stratégies (déjà en place ou nouvelles). Un aperçu historique est d'abord présenté, suivi d'une explication des démarches qui mènent à une stratégie de visualisation d'avenir. L'analyse de données de recherche provenant d'une étude pilote portant sur l'instrument permet de croire qu'il est plus probable que les chefs de file dans les écoles s'impliquent dans les stratégies de visualisation d'avenir que les parents ou les élèves. Globalement, toutes les parties intéressées et plus précisément, les parents, les élèves et les directeurs d'école, sont plus aptes à être impliqués dans les processus de visualisation dans les écoles de taille moyenne. Les chefs de file dans les écoles devront s'interroger pour savoir si les changements effectués dans leur école proviennent d'une vision qui a été mise sur pied par un processus inclusif et participatif ou s'ils sont le résultat de processus centralisés, mandatés et descendants tout simplement mis en œuvre par les directeurs d'école

Ensemble based quantum metrology

The field of quantum metrology promises measurement devices that are fundamentally superior to conventional technologies. Specifically, when quantum entanglement is harnessed the precision achieved is supposed to scale more favourably with the resources employed, such as system size and the time required. Here we consider measurement of magnetic field strength using an ensemble of spins, and we identify a third essential resource: the initial system polarisation, i.e. the low entropy of the original state. We find that performance depends crucially on the form of decoherence present; for a plausible dephasing model, we describe a quantum strategy which can indeed beat the standard quantum limit

Quantum metrology with molecular ensembles

This work was supported by the EPSRC through QIP IRC (Grants No. GR/S82176/01 and No. GR/S15808/01), the National Research Foundation and Ministry of Education, Singapore, the DAAD, and the Royal Society.The field of quantum metrology promisesmeasurement devices that are fundamentally superior to conventional technologies. Specifically, when quantum entanglement is harnessed, the precision achieved is supposed to scale more favorably with the resources employed, such as system size and time required. Here, we consider measurement of magnetic-field strength using an ensemble of spin-active molecules. We identify a third essential resource: the change in ensemble polarization (entropy increase) during the metrology experiment. We find that performance depends crucially on the form of decoherence present; for a plausible dephasing model, we describe a quantum strategy, which can indeed beat the standard strategy.Publisher PDFPeer reviewe

Dynamic analysis of a lithium-boiling potassium refractory metal Rankine cycle power system for the Jet Propulsion Laboratory

Lithium-boiling potassium refractory metal Rankine cycle power system heat transfer model

Earth resources-regional transfer activity contracts review

A regional transfer activity contracts review held by the Earth Resources Office was summarized. Contracts in the earth resources field primarily directed toward applications of satellite data and technology in solution of state and regional problems were reviewed. A summary of the progress of each contract was given in order to share experiences of researchers across a seven state region. The region included Missouri, Kentucky, Tennessee, Mississippi, Alabama, Georgia, and North Carolina. Research in several earth science disciplines included forestry, limnology, water resources, land use, geology, and mathematical modeling. The use of computers for establishment of information retrieval systems was also emphasized