Oviposition of Culex pipiens in water at different temperatures

At 20C air temperature, female <i>Culex pipiens</i> L. laid the greatest number of egg rafts at water temperatures between 20 and 25C. They laid very few at 15 or 35C even when given no alternative site. The possibility is discussed of manipulating temperature in a mosquito control programme

Reduction and analysis of photometric data on Comet Halley

The discovery that periodic variations in the brightness of Comet Halley were characterized by two unrelated frequencies implies that the nucleus is in a complex state of rotation. It either nutates as a result of the random addition of small torque perturbations accumulated over many perihelion passages, or the jet activity torques are so strong that it precesses wildly at each perihelion passage. To diagnose the state of nuclear rotation, researchers began a program to acquire photometric time series of the comet as it recedes from the sun. The intention is to observe the decay of the comet's atmosphere and then, when it is unemcumbered by the light of the coma, follow the light variation of the nucleus itself. The latter will be compared with preperihelion time series and the orientation of the nucleus at the time of Vega and Giotto flybys and an accurate rotational ephemeris constructed. Halley was observed on 38 nights during 1987 and approximately 21 nights in 1988. The comet moved from 5 AU to 8.5 AU during this time. The brightness of the coma was found to rapidly decrease in 1988 as the coma and cometary activity collapses. The magnitude in April 1988 was 19 mag (visual) and it is predicted that the nucleus itself will be the major contributor to the brightness in the 1988 and 1989 season

Critical learning incidents in system dynamics modelling engagements

This paper reports in-depth behavioural operational research to explore how individual clients learned to resolve dynamically complex problems in system dynamics model-based engagements. Consultant-client dyads were interviewed in ten system dynamics consulting engagements to identify individual clients' Critical Learning Incidents—defined as the moment of surprise caused after one's mental model produces unexpected failure and a change in one’s mental model produces the desired result. The cases are reprised from interviews and include assessments of the nature of the engagement problem, the form of system dynamics model, and the methods employed by consultants during each phase of the engagement. Reported Critical Learning Incidents are noted by engagement phase and consulting method, and constructivist learning theory is used to describe a pattern of learning. Outcomes of the research include describing the role of different methods applied in engagement phases (for example, the role of concept models to commence problem identification and to introduce iconography and jargon to the engagement participants), how model form associates with timings of Critical Learning Incidents, and the role of social mediation and negotiation in the learning process

Creation of 3D models from large unstructured image and video datasets

Exploration of various places using low-cost camera solutions over decades without having a photogrammetric application in mind has resulted in large collections of images and videos that may have significant cultural value. The purpose of collecting this data is often to provide a log of events and therefore the data is often unstructured and of varying quality. Depending on the equipment used there may be approximate location data available for the images but the accuracy of this data may also be of varying quality. In this paper we present an approach that can deal with these conditions and process datasets of this type to produce 3D models. Results from processing the dataset collected during the discovery and subsequent exploration of the HMAS Sydney and HSK Kormoran wreck sites shows the potential of our approach. The results are promising and show that there is potential to retrieve significantly more information from many of these datasets than previously thought possible

Qualitative Examination of African American Women's Perspectives about Depression

Gaining greater understanding about the various psychosocial, socio-cultural, and environmental factors that may influence experiences of depression among African American women (AAW) helps elucidate how this mental illness impacts the lives of this population. Sixty-three adult AAW comprised the study’s convenience sample.  Specifically, focus group cohorts inclusive of women from an academic institution, a primary healthcare clinic, and an urban community setting were conducted.  Results indicated six (6) dominant common themes as issues that may increase risk for depression among diverse AAW.  Similarities and differences about perspectives that contributed to depression were delineated among the three cohorts of AAW.  These results are important for mental/behavioral health researchers, practitioners, and public health professionals that are engaged in the design and implementation of culturally centered and gender-specific prevention and intervention strategies targeted to AAW at risk for depression. 

Strategy management through quantitative modelling of performance measurement systems

This paper is based on previous works on performance measurement and on quantification of relationships between factors which affect performance. It demonstrates how tools and techniques developed can be used to evaluate the performance of alternative strategic choices through a quantitative approach to modelling of performance measurement systems. The paper provides a brief background to the research problem and preceding works. The tools and techniques used are briefly introduced. Use of these tools and techniques to evaluate the performance of alternative manufacturing strategies is demonstrated. Finally, the capability of the approach to deal with dynamic environments is demonstrated using sensitivity analysis

Defining Remoteness from Health Care: Integrated Research on Accessing Emergency Maternal Care in Indonesia<br />

The causes of maternal death are well known, and are largely preventable if skilled health care is received promptly. Complex interactions between geographic and socio-cultural factors affect access to, and remoteness from, health care but research on this topic rarely integrates spatial and social sciences. In this study, modeling of travel time was integrated with social science research to refine our understanding of remoteness from health care. Travel time to health facilities offering emergency obstetric care (EmOC) and population distribution were modelled for a district in eastern Indonesia. As an index of remoteness, the proportion of the population more than two hours estimated travel time from EmOC was calculated. For the best case scenario (transport by ambulance in the dry season), modelling estimated more than 10,000 fertile aged women were more than two hours from EmOC. Maternal mortality ratios were positively correlated with the remoteness index, however there was considerable variation around this relationship. In a companion study, ethnographic research in a subdistrict with relatively good access to health care and high maternal mortality identified factors influencing access to EmOC, including some that had not been incorporated into the travel time model. Ethnographic research provided information about actual travel involved in requesting and reaching EmOC. Modeled travel time could be improved by incorporating time to deliver request for care. Further integration of social and spatial methods and the development of more dynamic travel time models are needed to develop programs and policies to address these multiple factors to improve maternal health outcomes

Oviposition of Culex pipiens in water at different temperatures

At 20C air temperature, female Culex pipiens L. laid the greatest number of egg rafts at water temperatures between 20 and 25C. They laid very few at 15 or 35C even when given no alternative site. The possibility is discussed of manipulating temperature in a mosquito control programme

The Cratering History of Asteroid (2867) Steins

The cratering history of main belt asteroid (2867) Steins has been investigated using OSIRIS imagery acquired during the Rosetta flyby that took place on the 5th of September 2008. For this purpose, we applied current models describing the formation and evolution of main belt asteroids, that provide the rate and velocity distributions of impactors. These models coupled with appropriate crater scaling laws, allow the cratering history to be estimated. Hence, we derive Steins' cratering retention age, namely the time lapsed since its formation or global surface reset. We also investigate the influence of various factors -like bulk structure and crater erasing- on the estimated age, which spans from a few hundred Myrs to more than 1Gyr, depending on the adopted scaling law and asteroid physical parameters. Moreover, a marked lack of craters smaller than about 0.6km has been found and interpreted as a result of a peculiar evolution of Steins cratering record, possibly related either to the formation of the 2.1km wide impact crater near the south pole or to YORP reshaping.Comment: Accepted by Planetary and Space Scienc