37 research outputs found

    Measurement of Aerosols at the Pierre Auger Observatory

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    The air fluorescence detectors (FDs) of the Pierre Auger Observatory are vital for the determination of the air shower energy scale. To compensate for variations in atmospheric conditions that affect the energy measurement, the Observatory operates an array of monitoring instruments to record hourly atmospheric conditions across the detector site, an area exceeding 3,000 square km. This paper presents results from four instruments used to characterize the aerosol component of the atmosphere: the Central Laser Facility (CLF), which provides the FDs with calibrated laser shots; the scanning backscatter lidars, which operate at three FD sites; the Aerosol Phase Function monitors (APFs), which measure the aerosol scattering cross section at two FD locations; and the Horizontal Attenuation Monitor (HAM), which measures the wavelength dependence of aerosol attenuation.Comment: Contribution to the 30th International Cosmic Ray Conference, Merida Mexico, July 2007; 4 pages, 4 figure

    Expert consensus document: Clinical and molecular diagnosis, screening and management of Beckwith-Wiedemann syndrome: an international consensus statement.

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    Beckwith-Wiedemann syndrome (BWS), a human genomic imprinting disorder, is characterized by phenotypic variability that might include overgrowth, macroglossia, abdominal wall defects, neonatal hypoglycaemia, lateralized overgrowth and predisposition to embryonal tumours. Delineation of the molecular defects within the imprinted 11p15.5 region can predict familial recurrence risks and the risk (and type) of embryonal tumour. Despite recent advances in knowledge, there is marked heterogeneity in clinical diagnostic criteria and care. As detailed in this Consensus Statement, an international consensus group agreed upon 72 recommendations for the clinical and molecular diagnosis and management of BWS, including comprehensive protocols for the molecular investigation, care and treatment of patients from the prenatal period to adulthood. The consensus recommendations apply to patients with Beckwith-Wiedemann spectrum (BWSp), covering classical BWS without a molecular diagnosis and BWS-related phenotypes with an 11p15.5 molecular anomaly. Although the consensus group recommends a tumour surveillance programme targeted by molecular subgroups, surveillance might differ according to the local health-care system (for example, in the United States), and the results of targeted and universal surveillance should be evaluated prospectively. International collaboration, including a prospective audit of the results of implementing these consensus recommendations, is required to expand the evidence base for the design of optimum care pathways

    Complex Processes from Dynamical Architectures with Time-Scale Hierarchy

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    The idea that complex motor, perceptual, and cognitive behaviors are composed of smaller units, which are somehow brought into a meaningful relation, permeates the biological and life sciences. However, no principled framework defining the constituent elementary processes has been developed to this date. Consequently, functional configurations (or architectures) relating elementary processes and external influences are mostly piecemeal formulations suitable to particular instances only. Here, we develop a general dynamical framework for distinct functional architectures characterized by the time-scale separation of their constituents and evaluate their efficiency. Thereto, we build on the (phase) flow of a system, which prescribes the temporal evolution of its state variables. The phase flow topology allows for the unambiguous classification of qualitatively distinct processes, which we consider to represent the functional units or modes within the dynamical architecture. Using the example of a composite movement we illustrate how different architectures can be characterized by their degree of time scale separation between the internal elements of the architecture (i.e. the functional modes) and external interventions. We reveal a tradeoff of the interactions between internal and external influences, which offers a theoretical justification for the efficient composition of complex processes out of non-trivial elementary processes or functional modes

    Time Scale Hierarchies in the Functional Organization of Complex Behaviors

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    Traditional approaches to cognitive modelling generally portray cognitive events in terms of ‘discrete’ states (point attractor dynamics) rather than in terms of processes, thereby neglecting the time structure of cognition. In contrast, more recent approaches explicitly address this temporal dimension, but typically provide no entry points into cognitive categorization of events and experiences. With the aim to incorporate both these aspects, we propose a framework for functional architectures. Our approach is grounded in the notion that arbitrary complex (human) behaviour is decomposable into functional modes (elementary units), which we conceptualize as low-dimensional dynamical objects (structured flows on manifolds). The ensemble of modes at an agent’s disposal constitutes his/her functional repertoire. The modes may be subjected to additional dynamics (termed operational signals), in particular, instantaneous inputs, and a mechanism that sequentially selects a mode so that it temporarily dominates the functional dynamics. The inputs and selection mechanisms act on faster and slower time scales then that inherent to the modes, respectively. The dynamics across the three time scales are coupled via feedback, rendering the entire architecture autonomous. We illustrate the functional architecture in the context of serial behaviour, namely cursive handwriting. Subsequently, we investigate the possibility of recovering the contributions of functional modes and operational signals from the output, which appears to be possible only when examining the output phase flow (i.e., not from trajectories in phase space or time)

    A comprehensive overview of radioguided surgery using gamma detection probe technology

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    The concept of radioguided surgery, which was first developed some 60 years ago, involves the use of a radiation detection probe system for the intraoperative detection of radionuclides. The use of gamma detection probe technology in radioguided surgery has tremendously expanded and has evolved into what is now considered an established discipline within the practice of surgery, revolutionizing the surgical management of many malignancies, including breast cancer, melanoma, and colorectal cancer, as well as the surgical management of parathyroid disease. The impact of radioguided surgery on the surgical management of cancer patients includes providing vital and real-time information to the surgeon regarding the location and extent of disease, as well as regarding the assessment of surgical resection margins. Additionally, it has allowed the surgeon to minimize the surgical invasiveness of many diagnostic and therapeutic procedures, while still maintaining maximum benefit to the cancer patient. In the current review, we have attempted to comprehensively evaluate the history, technical aspects, and clinical applications of radioguided surgery using gamma detection probe technology

    Multi-messenger observations of a binary neutron star merger

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    On 2017 August 17 a binary neutron star coalescence candidate (later designated GW170817) with merger time 12:41:04 UTC was observed through gravitational waves by the Advanced LIGO and Advanced Virgo detectors. The Fermi Gamma-ray Burst Monitor independently detected a gamma-ray burst (GRB 170817A) with a time delay of ~1.7 s with respect to the merger time. From the gravitational-wave signal, the source was initially localized to a sky region of 31 deg2 at a luminosity distance of 40+8-8 Mpc and with component masses consistent with neutron stars. The component masses were later measured to be in the range 0.86 to 2.26 Mo. An extensive observing campaign was launched across the electromagnetic spectrum leading to the discovery of a bright optical transient (SSS17a, now with the IAU identification of AT 2017gfo) in NGC 4993 (at ~40 Mpc) less than 11 hours after the merger by the One- Meter, Two Hemisphere (1M2H) team using the 1 m Swope Telescope. The optical transient was independently detected by multiple teams within an hour. Subsequent observations targeted the object and its environment. Early ultraviolet observations revealed a blue transient that faded within 48 hours. Optical and infrared observations showed a redward evolution over ~10 days. Following early non-detections, X-ray and radio emission were discovered at the transient’s position ~9 and ~16 days, respectively, after the merger. Both the X-ray and radio emission likely arise from a physical process that is distinct from the one that generates the UV/optical/near-infrared emission. No ultra-high-energy gamma-rays and no neutrino candidates consistent with the source were found in follow-up searches. These observations support the hypothesis that GW170817 was produced by the merger of two neutron stars in NGC4993 followed by a short gamma-ray burst (GRB 170817A) and a kilonova/macronova powered by the radioactive decay of r-process nuclei synthesized in the ejecta

    The complex remuneration of human resources for health in low-income settings: policy implications and a research agenda for designing effective financial incentives

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    Background Human resources for health represent an essential component of health systems and play a key role to accelerate progress towards universal health coverage. Many countries in sub-Saharan Africa face challenges regarding the availability, distribution and performance of health workers, which could be in part addressed by providing effective financial incentives. Methods Based on an overview of the existing literature, the paper highlights the gaps in the existing research in low-income countries exploring the different components of health workers' incomes. It then proposes a novel approach to the analysis of financial incentives and delineates a research agenda, which could contribute to shed light on this topic. Findings The article finds that, while there is ample research that investigates separately each of the incomes health workers may earn (for example, salary, fee-for-service payments, informal incomes, top-ups- and per diems, dual practice and non-health activities), there is a dearth of studies which look at the health workers' complex remuneration-, that is, the whole of the financial incentives available. Little research exists which analyses simultaneously all revenues of health workers, quantifies the overall remuneration and explores its complexity, its multiple components and their features, as well as the possible interaction between income components. However, such a comprehensive approach is essential to fully comprehend health workers' incentives, by investigating the causes (at individual and system level) of the fragmentation in the income structure and the variability in income levels, as well as the consequences of the complex remuneration- on motivation and performance. This proposition has important policy implications in terms of devising effective incentive packages as it calls for an active consideration of the role that complex remuneration- plays in determining recruitment, retention and motivation patterns, as well as, more broadly, the performance of health systems. Conclusions This paper argues that research focusing on the health workers' complex remuneration- is critical to address some of the most challenging issues affecting human resources for health. An empirical research agenda is proposed to fill the gap in our understanding.This article is about public relations expertise. It presents the results of an extensive empirical enquiry and is framed by the concept of profession and the sociological debates that surround it.sch_iih13pub3968pub6

    Hedonic Quality, Social Norms, and Environmental Campaigns

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    Mechanical Impedance and Its Relations to Motor Control, Limb Dynamics, and Motion Biomechanics

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    Some Factors Associated with Non – Adherence to Antiretroviral Therapy (ART) in People Living with HIV/AIDS (PLHA) in Tanzania: A Case Study of Dar es Salaam Region.

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    Objectives: Tanzania is one of the nations that are highly affected by HIV/AIDS epidemic. Invention of ARVs (Anti –Retroviral) brought hope of extended life to people living with HIV/AIDS (PLHA). Though ARV’s are administered in several clinics particularly in Dar es Salaam, there is a problem to adherence. Some factors associated with non-adherence are investigated and ways to optimize adherence are suggested.Methods: This study was undertaken at three treatment and care clinics in Dar es Salaam. A sample of 197 individuals on ARV and 30 health care providers were interviewed. The sample comprised of 76 % females and 24% males, with mean age 34. About 74% ofindividuals on ARV were aged between 25 – 45 years. Logistic Regression and survival analysis models were used in the analysis.Results: Individuals on ARV recommended factors responsible for non-adherence as lack of awareness 63.5%, stigma 56%, side effects 53.3%, and costs 28%. Other factors were being busy 25.4%, away from home 21.3%, forgetting 12.2% and ARVs out of stock 10.2%. Proportion of PLHA lost to follow up was 26%. Awareness and side effects were found to be statistically significant, with p-values of 0.042 and 0.068 respectively (a = 0.1). The median survival time for individuals on ARV was 42 months (95% CI: 41–44) with survival rate of above 0.7. Log-rank test showed significant differences between the male and female on having a shorter time to death. Females seemed to survive longer than males suggesting that females adhere more to ART than males.Conclusion: This calls for emphasis on HIV/AIDS education to the society especially to sensitize men. Another suggestion is that when a woman gets pregnant, both the expectant mother and father should attend maternal clinic so that they both take HIV test so as to increase man’s participation.Keywords: Non-adherence, Antiretroviral, HIV/AIDS, survival, men, wome
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