Low noise cryogenic dielectric resonator oscillator

A microwave oscillator is provided which can operate at a temperature of many degrees above absolute zero while providing very low phase noise that has heretofore generally required temperatures within a few degrees K. The oscillator includes a ring-shaped resonant element of ruby (sapphire plus chromium) or iron sapphire crystal, lying adjacent to a resonator element of sapphire, so that the regenerator element lies directly in the magnetic field of the resonator element. The resonator element is substantially devoid of contact with electrically conductive material. Microwave energy of a pump frequency (e.g., 31 GHz) is outputted from the regenerator element, while signal energy (e.g., 10 GHz) is outputted from the resonator element

A Planning Template for Nonwork Travel and Transit Oriented Development, MTI Report 01-12

The Mineta Transportation Institute (MTI) at San José State University assigned a project team to design a planning template for transit-oriented development (TOD) that incorporates an understanding of nonwork travel, that is, trips for shopping, eating out, and engaging in recreational and cultural activities. Nonwork trips are growing in signifigance and now account for four of every five trips. At the same time, TOD has become a popular planning response to the impacts of metropolitan growth. Some planners believe that TOD will induce more pedestrian and transit trips and will reduce the average length and frequency of household auto travel. This effect is assumed to result from improved accessibility to employment and nonwork venues located in compact, mixed-use centers. Planning professionals in many MPOs also suggest that if multiple centers are linked by high quality transit, such as light or heavy rail, access is enabled to the broad range of nonwork activities. The project arrived at these essential findings: (1) Venues for nonwork activities are very numerous and geographically dispersed. 2) The spatial environment for nonwork activities is the result of growing prosperity, technical innovation, and a dynamic, competitive marketplace. (3) The consumer marketplace will provide many more places to go than mass transit can cost-effectively serve. (4) Current metropolitan planning methods and modeling tools focus on the work trip and do not adequately account for the complexity of nonwork trips and their linkage to work trips. These findings support the need for a new regional planning process to complement current methods. One recommended approach is that metropolitan communities establish a Nonwork Travel Improvement Planning Process using a multidisciplinary expert advisory group interacting with a core, Internet-enabled, professional transportation planning staff. An iterative interaction across varied but relevant skill sets could be achieved through a Backcasting Delphi process. The focus of the interaction would be on understanding the ramifications of consumer and retail industry behavior for TOD and other new transportation strategies, and then assessing the available strategies for cost-effectiveness in reducing the impacts of growth and automobility in a complex and uncertain metropolitan market

Assessing the painful, uninflamed eye in primary care

We acknowledge the important contributions of Professor Amada J Lee, University of Aberdeen, Division of Statistics, for assistance with analysing the data from the patient survey. We thank Kamran Khan, Oliver Chadwick, and Paul Chua, trainee ophthalmologists, NHS Grampian, for providing the clinical images. Contributors: LK contributed to the design of the study, the survey of patients, and writing the paper. JVF contributed to the design of the study and writing the paper. ADD contributed to the design of the study, the survey of the patients, and writing the paper. JVF is guarantor for the paper.Peer reviewedPublisher PD

Autoimmunity, Autoinflammation, and Infection in Uveitis

Funding/Support: No funding or grant support. Financial Disclosures: John V. Forrester has received an honorarium for lecturing from Janssen (London, UK). Lucia Kuffova has undertaken consultancy work for Abbvie (London, UK). Andrew D. Dick has undertaken consultancy work for Abbvie (London, UK), Roche (London, UK), and Genentech (London, UK) and has received honoraria from Janssen (London, UK) and Abbvie (London, UK). The authors attest that they meet the current ICMJE criteria for authorship.Peer reviewedPublisher PD

Results from the Scottish report card on physical activity for children and youth

The Active Healthy Kids Scotland Report Card aims to consolidate existing evidence, facilitate international comparisons, encourage more evidence-informed physical activity and health policy, and improve surveillance of physical activity. Application of the Active Healthy Kids Canada Report Card process and methodology to Scotland, adapted to Scottish circumstances and availability of data. The Active Healthy Kids Scotland Report Card 2013 consists of indicators of 7 Health Behaviors and Outcomes and 3 Influences on Health Behaviors and Outcomes. Grades of F were assigned to Overall Physical Activity, Sedentary Behavior (recreational screen time), and Obesity Prevalence. A C was assigned to Active Transportation and a D- was assigned to Diet. Two indicators, Active and Outdoor Play and Organized Sport Participation, could not be graded. Among the Influences, Family Influence received a D, while Perceived Safety, Access, and Availability of Spaces for Physical Activity and the National Policy Environment graded more favorably with a B. The Active Healthy Kids Canada process and methodology was readily generalizable to Scotland. The report card illustrated low habitual physical activity and extremely high levels of screen-based sedentary behavior, and highlighted several opportunities for improved physical activity surveillance and promotion strategies

Deconstruction of compound objects from image sets

We propose a method to recover the structure of a compound object from multiple silhouettes. Structure is expressed as a collection of 3D primitives chosen from a pre-defined library, each with an associated pose. This has several advantages over a volume or mesh representation both for estimation and the utility of the recovered model. The main challenge in recovering such a model is the combinatorial number of possible arrangements of parts. We address this issue by exploiting the sparse nature of the problem, and show that our method scales to objects constructed from large libraries of parts

Taste Heterogeneity and Substitution Patterns in Models of the Simultaneous Choice of Activity Timing and Duration

The recent growth of interest in activity-based methods has focused particular attention on travellers’ decision making regarding the timing and duration of their participation in activities. However, to date these two dimensions of activity participation have been largely treated separately. It is clear, however, that in general, the benefit that an individual derives from participating in an activity will depend inter alia both upon the time at which the activity is undertaken and the amount of time devoted to the activity. Moreover, it is also clear that this benefit will also depend on a wide range of other factors such as the quality of the activity opportunities available at particular destinations and the intensity with which activities are undertaken. Since these factors are inherently difficult or impossible to completely characterise or measure via conventional travel or time use data sources, it is likely that such decisions will also be characterised by significant unobserved heterogeneity. Based on earlier theoretical work by the authors, this paper proposes a model for the simultaneous choice of the timing and duration of activities and associated travel and uses data from a stated preference experiment to estimate the parameters of this model. The first section of the paper provides a brief review of the existing literature on activity timing and duration choice. The second section introduces the theoretical approach, which assume that the marginal utility derived from activities encompasses two distinct components; one derived from the duration of activity involvement and the other derived from activity participation at a particular time-of-day. A number of alternative additive and multiplicative specifications are introduced and their properties are explored. The third section briefly describes the stated preference data, which was collected in a survey undertaken in London in which respondents were presented with a number of scenarios in which they were asked to choose between alternative tours involving a single destination activity. The timing and duration both of the destination activity and the associated travel varied across scenarios. The fourth section discusses the empirical specification and estimation of the model and presents the estimation results. This uses an error-components formulation of the mixed multinomial logit model to account both for unobserved heterogeneity in tastes and for heteroskedascity and complex substitution patterns amongst activity alternatives. Particular attention is given to the use of advanced optimisation techniques needed to estimate the non-linear utility function expressing individuals’ timing and duration preferences.The fifth section discusses the significance of the results and their potential application to a number of practical transport planning problems including the prediction of user response to travel demand management policies and accessibility planning. The paper closes with some overall conclusions and a discussion of future research directions.

Is Success Hereditary? Evidence on the Performance of Spawned Ventures

A common phenomenon in entrepreneurship is that employees turn away from employmentto found their own businesses. Prior literature discusses the former employers’characteristics that influence the creation of entrepreneurial ventures. An investigation ofwhether these characteristics also affect the success of the spawned ventures is missing so far. This paper contributes to the literature by showing that entrepreneurial ventures spawned by well performing firms are financially more successful than ventures stemming from bad performing firms. This suggests that spawned entrepreneurs are able to exploit valuable knowledge from their previous employers which impacts their ventures’ performance positively. The analysis is based on a linked employee-employer dataset for the Netherlands for the period 1999-2004.Strategy;