82 research outputs found

    Scintillation-limited photometry with the 20-cm NGTS telescopes at Paranal Observatory

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    Ground-based photometry of bright stars is expected to be limited by atmospheric scintillation, although in practice observations are often limited by other sources of systematic noise. We analyse 122 nights of bright star (Gmag ≲ 11.5) photometry using the 20-cm telescopes of the Next-Generation Transit Survey (NGTS) at the Paranal Observatory in Chile. We compare the noise properties to theoretical noise models and we demonstrate that NGTS photometry of bright stars is indeed limited by atmospheric scintillation. We determine a median scintillation coefficient at the Paranal Observatory of CY=1.54⁠, which is in good agreement with previous results derived from turbulence profiling measurements at the observatory. We find that separate NGTS telescopes make consistent measurements of scintillation when simultaneously monitoring the same field. Using contemporaneous meteorological data, we find that higher wind speeds at the tropopause correlate with a decrease in long-exposure (t = 10 s) scintillation. Hence, the winter months between June and August provide the best conditions for high-precision photometry of bright stars at the Paranal Observatory. This work demonstrates that NGTS photometric data, collected for searching for exoplanets, contains within it a record of the scintillation conditions at Paranal

    Concert recording 2016-04-03

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    [Track 01]. Fanfare pour précéder \u27La Péri\u27 / Paul Dukas -- [Track 02]. French dances revisted. I ; [Track 03]. II ; [Track 04]. III ; [Track 05]. IV ; [Track 06]. V ; [Track 07]. VI / Adam Gorb -- [Track 08]. Danses sacrée et profane / Claude Debussy -- [Track 09]. Dance mix / Rob Smith

    Global agricultural intensification during climate change: a role for genomics

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    Agriculture is now facing the ‘perfect storm’ of climate change, increasing costs of fertilizer and rising food demands from a larger and wealthier human population. These factors point to a global food deficit unless the efficiency and resilience of crop production is increased. The intensification of agriculture has focused on improving production under optimized conditions, with significant agronomic inputs. Furthermore, the intensive cultivation of a limited number of crops has drastically narrowed the number of plant species humans rely on. A new agricultural paradigm is required, reducing dependence on high inputs and increasing crop diversity, yield stability and environmental resilience. Genomics offers unprecedented opportunities to increase crop yield, quality and stability of production through advanced breeding strategies, enhancing the resilience of major crops to climate variability, and increasing the productivity and range of minor crops to diversify the food supply. Here we review the state of the art of genomic-assisted breeding for the most important staples that feed the world, and how to use and adapt such genomic tools to accelerate development of both major and minor crops with desired traits that enhance adaptation to, or mitigate the effects of climate change

    Introduction to A Compendium of Strategies to Prevent Healthcare-Associated Infections In Acute-Care Hospitals: 2022 Updates.

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    Since the initial publication of A Compendium of Strategies to Prevent Healthcare-Associated Infections in Acute Care Hospitals in 2008, the prevention of healthcare-associated infections (HAIs) has continued to be a national priority. Progress in healthcare epidemiology, infection prevention, antimicrobial stewardship, and implementation science research has led to improvements in our understanding of effective strategies for HAI prevention. Despite these advances, HAIs continue to affect ∼1 of every 31 hospitalized patients, leading to substantial morbidity, mortality, and excess healthcare expenditures, and persistent gaps remain between what is recommended and what is practiced.The widespread impact of the coronavirus disease 2019 (COVID-19) pandemic on HAI outcomes in acute-care hospitals has further highlighted the essential role of infection prevention programs and the critical importance of prioritizing efforts that can be sustained even in the face of resource requirements from COVID-19 and future infectious diseases crises.The Compendium: 2022 Updates document provides acute-care hospitals with up-to-date, practical expert guidance to assist in prioritizing and implementing HAI prevention efforts. It is the product of a highly collaborative effort led by the Society for Healthcare Epidemiology of America (SHEA), the Infectious Disease Society of America (IDSA), the Association for Professionals in Infection Control and Epidemiology (APIC), the American Hospital Association (AHA), and The Joint Commission, with major contributions from representatives of organizations and societies with content expertise, including the Centers for Disease Control and Prevention (CDC), the Pediatric Infectious Disease Society (PIDS), the Society for Critical Care Medicine (SCCM), the Society for Hospital Medicine (SHM), the Surgical Infection Society (SIS), and others

    A Computational Approach to Understand In Vitro Alveolar Morphogenesis

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    Primary human alveolar type II (AT II) epithelial cells maintained in Matrigel cultures form alveolar-like cysts (ALCs) using a cytogenesis mechanism that is different from that of other studied epithelial cell types: neither proliferation nor death is involved. During ALC formation, AT II cells engage simultaneously in fundamentally different, but not fully characterized activities. Mechanisms enabling these activities and the roles they play during different process stages are virtually unknown. Identifying, characterizing, and understanding the activities and mechanisms are essential to achieving deeper insight into this fundamental feature of morphogenesis. That deeper insight is needed to answer important questions. When and how does an AT cell choose to switch from one activity to another? Why does it choose one action rather than another? We report obtaining plausible answers using a rigorous, multi-attribute modeling and simulation approach that leveraged earlier efforts by using new, agent and object-oriented capabilities. We discovered a set of cell-level operating principles that enabled in silico cells to self-organize and generate systemic cystogenesis phenomena that are quantitatively indistinguishable from those observed in vitro. Success required that the cell components be quasi-autonomous. As simulation time advances, each in silico cell autonomously updates its environment information to reclassify its condition. It then uses the axiomatic operating principles to execute just one action for each possible condition. The quasi-autonomous actions of individual in silico cells were sufficient for developing stable cyst-like structures. The results strengthen in silico to in vitro mappings at three levels: mechanisms, behaviors, and operating principles, thereby achieving a degree of validation and enabling answering the questions posed. We suggest that the in silico operating principles presented may have a biological counterpart and that a semiquantitative mapping exists between in silico causal events and in vitro causal events

    Photobiomodulation in the management of oral mucositis for adult head and neck cancer patients receiving irradiation: the LiTEFORM RCT.

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    BackgroundOral mucositis is a debilitating and painful complication of head and neck cancer irradiation that is characterised by inflammation of the mucous membranes, erythema and ulceration. Oral mucositis affects 6000 head and neck cancer patients per year in England and Wales. Current treatments have not proven to be effective. International studies suggest that low-level laser therapy may be an effective treatment.ObjectivesTo assess the clinical effectiveness and cost-effectiveness of low-level laser therapy in the management of oral mucositis in head and neck cancer irradiation. To identify barriers to and facilitators of implementing low-level laser therapy in routine care.DesignPlacebo-controlled, individually randomised, multicentre Phase III superiority trial, with an internal pilot and health economic and qualitative process evaluations. The participants, outcome assessors and therapists were blinded.SettingNine NHS head and neck cancer sites in England and Wales.ParticipantsA total of 87 out of 380 participants were recruited who were aged ≥ 18 years and were undergoing head and neck cancer irradiation with ≥ 60 Gy.InterventionRandom allocation (1 : 1 ratio) to either low-level laser therapy or sham low-level laser therapy three times per week for the duration of irradiation. The diode laser had the following specifications: wavelength 660 nm, power output 75 mW, beam area 1.5 cm2, irradiance 50 mW/cm2, exposure time 60 seconds and fluence 3 J/cm2. There were 20-30 spots per session. Sham low-level laser therapy was delivered in an identical manner.Main outcome measureThe mean Oral Mucositis Weekly Questionnaire-Head and Neck Cancer score at 6 weeks following the start of irradiation. Higher scores indicate a worse outcome.ResultsA total of 231 patients were screened and, of these, 87 were randomised (low-level laser therapy arm, n = 44; sham arm, n = 43). The mean age was 59.4 years (standard deviation 8.8 years) and 69 participants (79%) were male. The mean Oral Mucositis Weekly Questionnaire-Head and Neck Cancer score at 6 weeks was 33.2 (standard deviation 10) in the low-level laser therapy arm and 27.4 (standard deviation 13.8) in the sham arm.LimitationsThe trial lacked statistical power because it did not meet the recruitment target. Staff and patients willingly participated in the trial and worked hard to make the LiTEFORM trial succeed. However, the task of introducing, embedding and sustaining new low-level laser therapy services into a complex care pathway proved challenging. Sites could deliver low-level laser therapy to only a small number of patients at a time. The administration of low-level laser therapy was viewed as straightforward, but also time-consuming and sometimes uncomfortable for both patients and staff, particularly those staff who were not used to working in a patient's mouth.ConclusionsThis trial had a robust design but lacked power to be definitive. Low-level laser therapy is relatively inexpensive. In contrast with previous trials, some patients found low-level laser therapy sessions to be difficult. The duration of low-level laser therapy sessions is, therefore, an important consideration. Clinicians experienced in oral cavity work most readily adapt to delivering low-level laser therapy, although other allied health professionals can be trained. Blinding the clinicians delivering low-level laser therapy is feasible. There are important human resource, real estate and logistical considerations for those setting up low-level laser therapy services.Future workFurther well-designed randomised controlled trials investigating low-level laser therapy in head and neck cancer irradiation are needed, with similar powered recruitment targets but addressing the recruitment challenges and logistical findings from this research.Trial registrationThis trial is registered as ISRCTN14224600.FundingThis project was funded by the National Institute for Health and Care Research ( NIHR ) Health Technology Assessment programme and will be published in full in Health Technology Assessment; Vol. 26, No. 46. See the NIHR Journals Library website for further project information
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