670 research outputs found

    How do public programmes shape strategic R&D collaborations? Project-level evidence from the 5th and 6th EU Framework Programmes.

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    We analyze the micro rationale of EU-sponsored collaborations compared to non-sponsored, spontaneous collaborations. We compare the incentives and coordination mechanisms of each type of collaboration, and derive propositions that we test empirically. Our econometric analysis uses recent data on (sponsored and non-sponsored) projects conducted by participants in the 5th and 6th European R&D Framework Programmes. Our empirical findings support our main propositions. Compared to spontaneous collaborations, EU-sponsored collaborations clearly have different characteristics and follow a different rationale. However, there is no major difference between the different types of EU-sponsored collaborations.Strategic R&D Collaborations; European Framework Programmes; Research Joint Ventures.

    Constructing a gazebo: supporting teamwork in a tightly coupled, distributed task in virtual reality

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    Many tasks require teamwork. Team members may work concurrently, but there must be some occasions of coming together. Collaborative virtual environments (CVEs) allow distributed teams to come together across distance to share a task. Studies of CVE systems have tended to focus on the sense of presence or copresence with other people. They have avoided studying close interaction between us-ers, such as the shared manipulation of objects, because CVEs suffer from inherent network delays and often have cumbersome user interfaces. Little is known about the ef-fectiveness of collaboration in tasks requiring various forms of object sharing and, in particular, the concurrent manipu-lation of objects. This paper investigates the effectiveness of supporting teamwork among a geographically distributed group in a task that requires the shared manipulation of objects. To complete the task, users must share objects through con-current manipulation of both the same and distinct at-tributes. The effectiveness of teamwork is measured in terms of time taken to achieve each step, as well as the impression of users. The effect of interface is examined by comparing various combinations of walk-in cubic immersive projection technology (IPT) displays and desktop devices

    A study of event traffic during the shared manipulation of objects within a collaborative virtual environment

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    Event management must balance consistency and responsiveness above the requirements of shared object interaction within a Collaborative Virtual Environment (CVE) system. An understanding of the event traffic during collaborative tasks helps in the design of all aspects of a CVE system. The application, user activity, the display interface, and the network resources, all play a part in determining the characteristics of event management. Linked cubic displays lend themselves well to supporting natural social human communication between remote users. To allow users to communicate naturally and subconsciously, continuous and detailed tracking is necessary. This, however, is hard to balance with the real-time consistency constraints of general shared object interaction. This paper aims to explain these issues through a detailed examination of event traffic produced by a typical CVE, using both immersive and desktop displays, while supporting a variety of collaborative activities. We analyze event traffic during a highly collaborative task requiring various forms of shared object manipulation, including the concurrent manipulation of a shared object. Event sources are categorized and the influence of the form of object sharing as well as the display device interface are detailed. With the presented findings the paper wishes to aid the design of future systems

    Supporting a Closely Coupled Task between a Distributed Team: Using Immersive Virtual Reality Technology

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    Collaboration and teamwork is important in many areas of our lives. People come together to share and discuss ideas, split and distribute work or help and support each other. The sharing of information and artefacts is a central part of collaboration. This often involves the manipulation of shared objects, both sequentially as well as concurrently. For coordinating an efficient collaboration, communication between the team members is necessary. This can happen verbally in form of speech or text and non-verbally through gesturing, pointing, gaze or facial expressions and the referencing and manipulation of shared objects. Collaborative Virtual Environments (CVE) allow remote users to come together and interact with each other and virtual objects within a computer simulated environment. Immersive display interfaces, such as a walk-in display (e.g. CAVE), that place a human physically into the synthetic environment, lend themselves well to support a natural manipulation of objects as well a set of natural non-verbal human communication, as they can both capture and display human movement. Communication of tracking data, however, can saturate the network and result in delay or loss of messages vital to the manipulation of shared objects. This paper investigates the reality of shared object manipulation between remote users collaborating through linked walk-in displays and extends our research in [27]. Various forms of shared interaction are examined through a set of structured sub tasks within a representative construction task. We report on extensive user-trials between three walk-in displays in the UK and Austria linked over the Internet using a CVE, and demonstrate such effects on a naive implementation of a benchmark application, the Gazebo building task. We then present and evaluate application-level workarounds and conclude by suggesting solutions that may be implemented within next-generation CVE infrastructures

    Complications of retroperitoneoscopic living donor nephrectomy: single center experience after 164 cases

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    Objectives: Retroperitoneoscopic living donor nephrectomy (RLDN) is used by only a few centers worldwide. Similar to laparoscopic living donor nephrectomy it offers the donor rapid convalescence and excellent cosmetic results. However, concerns have been expressed over the safety of endoscopic living donor nephrectomy. Methods: We review the results of 164 consecutive RLDN from November 2001 to November 2007. Complications were classified into intra- and early postoperative. Results: Mean donor age was 53.4Ā±10.7years (27-79). Left kidneys were harvested in 76% of cases. Mean operation time was 146Ā±44min (55-270), and warm ischemia time 131Ā±45s (50-280). In two patients (1.2%) conversion to open nephrectomy was necessary. The intraoperative complication rate was 3.0%. In the postoperative period we observed in 17.7% minor complications with no persisting impairments for the donor. The rate of major complications in the early postoperative period was 4.3%. Three patients (1.8%) necessitated revision, due to laceration of the external iliac artery in one patient and chyloretroperitoneum in two patients. Mean donor creatinine was 113.1Ā±26.6mg/dl (63-201) on the first postoperative day, and 102.0Ā±22.2mg/dl (68-159) on the fifth postoperative day. Conclusion: Retroperitoneoscopic living donor nephrectomy can be performed with acceptable intraoperative and early postoperative morbidity. Operation times and warm ischemia times are comparable to the open approac

    Lessons Learned for the Assessment of Childrenā€™s Pesticide Exposure: Critical Sampling and Analytical Issues for Future Studies

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    In this article we examine sampling strategies and analytical methods used in a series of recent studies of childrenā€™s exposure to pesticides that may prove useful in the design and implementation of the National Childrenā€™s Study. We focus primarily on the experiences of four of the National Institute of Environmental Health Sciences/U.S. Environmental Protection Agency/ Childrenā€™s Centers and include University of Washington studies that predated these centers. These studies have measured maternal exposures, perinatal exposures, infant and toddler exposures, and exposure among young children through biologic monitoring, personal sampling, and environmental monitoring. Biologic monitoring appears to be the best available method for assessment of childrenā€™s exposure to pesticides, with some limitations. It is likely that a combination of biomarkers, environmental measurements, and questionnaires will be needed after careful consideration of the specific hypotheses posed by investigators and the limitations of each exposure metric. The value of environmental measurements, such as surface and toy wipes and indoor air or house dust samples, deserves further investigation. Emphasis on personal rather than environmental sampling in conjunction with urine or blood sampling is likely to be most effective at classifying exposure. For infants and young children, ease of urine collection (possible for extended periods of time) may make these samples the best available approach to capturing exposure variability of nonpersistent pesticides; additional validation studies are needed. Saliva measurements of pesticides, if feasible, would overcome the limitations of urinary metabolite-based exposure analysis. Global positioning system technology appears promising in the delineation of childrenā€™s timeā€“location patterns

    Workshop to identify critical windows of exposure for children's health: cancer work group summary.

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    We considered whether there are discrete windows of vulnerability in the development of cancer and which time periods may be of the greatest importance. Cancer was considered broadly, including cancers in childhood as well as adult cancers that may have an in utero or childhood origin. We concluded that there was evidence from animal and epidemiologic studies for causal relationships for preconceptional, in utero, and childhood exposures and cancer occurrence in children and adults. However, the evidence is incomplete and all relevant critical windows may not have been identified. The comprehensive evaluation of the relative importance of specific time windows of exposure is limited. Improvements in the design of epidemiologic studies and additional animal studies of mechanisms are warranted

    Retroperitoneoscopic donor nephrectomy: donor outcome and complication rate in comparison with three different techniques

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    Four surgical techniques for living donor nephrectomy were analyzed retrospectively in terms of perioperative outcome and early complication rate. A total of 182 donor nephrectomies including 69 open (OLDN), 14 fully laparoscopic (LDN), 34 hand-assisted laparoscopic (HLDN) and 65 retroperitoneoscopic (RLDN) nephrectomies were analyzed. There was a significant difference in mean operating time (OPT) between the OLDN (160min) and RLDN (150min) as compared to the LDN (212min) and HLDN group (192min) (P<0.001). Mean warm ischemia time (WIT) was significantly shorter with OLDN (114s), RLDN (121s) and HLDN (128s) when compared to LDN (238s) (P<0.001). Major complication rate was comparable among the groups. Independent of the preferred technique, donor nephrectomy is associated with complication rates. RLDN is comparable to OLDN in terms of OPT, WIT. Learning endoscopic donor nephrectomy could be associated with a higher complication rat
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