108 research outputs found

    Polariton condensation and lasing in optical microcavities - the decoherence driven crossover

    Full text link
    We explore the behaviour of a system which consists of a photon mode dipole coupled to a medium of two-level oscillators in a microcavity in the presence of decoherence. We consider two types of decoherence processes which are analogous to magnetic and non-magnetic impurities in superconductors. We study different phases of this system as the decoherence strength and the excitation density is changed. For a low decoherence we obtain a polariton condensate with comparable excitonic and photonic parts at low densities and a BCS-like state with bigger photon component due to the fermionic phase space filling effect at high densities. In both cases there is a large gap in the density of states. As the decoherence is increased the gap is broadened and suppressed, resulting in a gapless condensate and finally a suppression of the coherence in a low density regime and a laser at high density limit. A crossover between these regimes is studied in a self-consistent way analogous to the Abrikosov and Gor'kov theory of gapless superconductivity.Comment: 17 pages, 8 figures, submitted to PR

    Interspecies discrimination of A. fumigatus and siblings A. lentulus and A. felis of the Aspergillus section Fumigati using the AsperGenius® assay

    Get PDF
    The AsperGenius® assay detects several Aspergillus species and the A. fumigatus Cyp51A mutations TR34/L98H/T289A/Y121F that are associated with azole resistance. We evaluated its contribution in identifying A. lentulus and A. felis, 2 rare but intrinsically azole-resistant sibling species within the Aspergillus section Fumigati. Identification of these species with conventional culture techniques is difficult and time-consuming. The assay was tested on (i) 2 A. lentulus and A. felis strains obtained from biopsy proven invasive aspergillosis and (ii) control A. fumigatus (n=3), A. lentulus (n=6) and A. felis species complex (n=12) strains. The AsperGenius® resistance PCR did not detect the TR34 target in A. lentulus and A. felis in contrast to A. fumigatus. Melting peaks for L98H and Y121F markers differed and those of the Y121F marker were particularly suitable to discriminate the 3 species. In conclusion, the assay can be used to rapidly discriminate A. fumigatus, A. lentulus and A. felis.

    Scale in object and process ontologies

    Get PDF
    Scale is of great importance to the analysis of real world phenomena, be they enduring objects or perduring processes. This paper presents a new perspective on the concept of scale by considering it within two complementary ontological views. The first, called SNAP, recognizes enduring entities or objects, the other, called SPAN, perduring entities or processes. Within the meta-theory provided by the complementary SNAP and SPAN ontologies, we apply different theories of formal ontology such as mereology and granular partitions, and ideas derived from hierarchy theory. These theories are applied to objects and processes and form the framework within which we present tentative definitions of scale, which are found to differ between the two ontologies

    On Spatially Distributed Hydrological Ecosystem Services: Bridging the Quantitative Information Gap using Remote Sensing and Hydrological Models

    Get PDF
    One of the ways in which the CGIAR Research Program on Water, Land and Ecosystems (WLE) addresses the challenge of achieving sustainable growth is by improving our understanding of tradeoffs and synergies related to water, food, environment and energy. Essential to the success of these efforts is the availability of quantitative data on these tradeoffs and synergies, and how they vary across space and time. Specifically for the countries sharing the Mekong River, WLE Greater Mekong seeks to drive and inform research and dialogue around the rivers of the region. Hydrological EcoSystem Services (HESS) are heavily affected by intensive development across the region, such as the construction of hydropower dams and land use changes - in particular deforestation, urbanization and agricultural intensification. The full extent of such changes in the agro-ecological system is often unknown, and it is a challenge to account for tradeoffs in HESS in policy processes. As in many other areas of the world, improving governance and management of water resources and associated land and ecosystems in the Greater Mekong region is not only a matter of generating more data. Sharing of knowledge and practices is a key focus of WLE Greater Mekong, which we strive to promote by enhancing the accessibility of valuable information to a wide diversity of regional stakeholders, and promoting dialogue by facilitating the creation of communities of practice. This white paper demonstrates state-of-the-art methods for assessing different HESS and their tradeoffs under different development scenarios. It explores opportunities for spatial monitoring of HESS and predicting changes under different future scenarios, information that is essential for achieving a balanced and healthy agro-ecological system. By relying on tools in the public domain and leveraging the resulting HESS data through online information platforms, this white paper is an excellent example of current efforts supported by WLE Greater Mekong to stimulate uptake of ecosystem services assessments in decision-making processes

    Twelve-year outcomes of watchful waiting versus surgery of mildly symptomatic or asymptomatic inguinal hernia in men aged 50 years and older:a randomised controlled trial

    Get PDF
    Background: Inguinal hernia belongs to the most common surgical pathology worldwide. Approximately, one third is asymptomatic. The value of watchful waiting (WW) in patients with asymptomatic or mildly symptomatic inguinal hernia has been established in a few randomised controlled trials (RCTs). The aim of this study was to assess long-term outcomes of a RCT comparing WW and elective surgery.Methods: In the original study, men aged ≥50 years with an asymptomatic or mildly symptomatic inguinal hernia were randomly assigned to WW or elective repair. In the present study, the primary outcome was the 12-year crossover rate to surgery, secondary outcomes were time-to-crossover, patient regret, pain, quality of life and incarceration. Dutch Trial Registry: NTR629. Findings: Out of 496 originally analysed patients, 488 (98.4%) were evaluable for chart review (WW: n = 258, surgery: n = 230), and 200 (41.0%) for telephone contact (WW: n = 106, surgery: n = 94) between November 2021 and March 2022 with a median 12 years follow-up (IQR 9–14). After 12 years, the estimated cumulative crossover rate to surgery was 64.2%, which was higher in mildly symptomatic than in asymptomatic patients (71.7% versus 60.4%, HR 1.451, 95% CI: 1.064–1.979). Time-to-crossover was longer in asymptomatic patients (50% after 6.0 years versus 2.0 years, p = 0.019). Patient regret was higher in the WW group (37.7 versus 18.0%, p = 0.002), as well as pain/discomfort (p = 0.031). Quality of life did not differ (p = 0.737). In the WW group, incarceration occurred in 10/255 patients (3.9%). Interpretation: During 12-year follow-up, most WW patients crossed over to surgery, significantly earlier with mildly symptomatic hernia. Considering the relatively low incarceration rate, WW might still be an option in asymptomatic patients with a clear preference and being well-informed about pros and cons.</p

    Twelve-year outcomes of watchful waiting versus surgery of mildly symptomatic or asymptomatic inguinal hernia in men aged 50 years and older:a randomised controlled trial

    Get PDF
    Background: Inguinal hernia belongs to the most common surgical pathology worldwide. Approximately, one third is asymptomatic. The value of watchful waiting (WW) in patients with asymptomatic or mildly symptomatic inguinal hernia has been established in a few randomised controlled trials (RCTs). The aim of this study was to assess long-term outcomes of a RCT comparing WW and elective surgery. Methods: In the original study, men aged ≥50 years with an asymptomatic or mildly symptomatic inguinal hernia were randomly assigned to WW or elective repair. In the present study, the primary outcome was the 12-year crossover rate to surgery, secondary outcomes were time-to-crossover, patient regret, pain, quality of life and incarceration. Dutch Trial Registry: NTR629. Findings: Out of 496 originally analysed patients, 488 (98.4%) were evaluable for chart review (WW: n = 258, surgery: n = 230), and 200 (41.0%) for telephone contact (WW: n = 106, surgery: n = 94) between November 2021 and March 2022 with a median 12 years follow-up (IQR 9–14). After 12 years, the estimated cumulative crossover rate to surgery was 64.2%, which was higher in mildly symptomatic than in asymptomatic patients (71.7% versus 60.4%, HR 1.451, 95% CI: 1.064–1.979). Time-to-crossover was longer in asymptomatic patients (50% after 6.0 years versus 2.0 years, p = 0.019). Patient regret was higher in the WW group (37.7 versus 18.0%, p = 0.002), as well as pain/discomfort (p = 0.031). Quality of life did not differ (p = 0.737). In the WW group, incarceration occurred in 10/255 patients (3.9%). Interpretation: During 12-year follow-up, most WW patients crossed over to surgery, significantly earlier with mildly symptomatic hernia. Considering the relatively low incarceration rate, WW might still be an option in asymptomatic patients with a clear preference and being well-informed about pros and cons. Funding: The initial trial was funded by the Netherlands Organisation for Health Research and Development (ZonMW). This long-term study did not receive funding.</p

    Large-scale ICU data sharing for global collaboration: the first 1633 critically ill COVID-19 patients in the Dutch Data Warehouse

    Get PDF
    • …
    corecore