The British Society of Gastroenterology (BSG) and the Association of Coloproctology for Great Britain and Ireland (ACPGBI) commissioned this update of the 2002 guidance. The aim, as before, is to ...provide guidance on the appropriateness, method and frequency of screening for people at moderate and high risk from colorectal cancer. This guidance provides some new recommendations for those with inflammatory bowel disease and for those at moderate risk resulting from a family history of colorectal cancer. In other areas guidance is relatively unchanged, but the recent literature was reviewed and is included where appropriate.
ABSTRACT
In the two decades since the first extra‐solar planet was discovered, the detection and characterization of extra‐solar planets has become one of the key endeavours in all of modern science. ...Recently, direct detection techniques such as interferometry or coronagraphy have received growing attention because they reveal the population of exoplanets inaccessible to Doppler or transit techniques, and moreover they allow the faint signal from the planet itself to be investigated. Next‐generation stellar interferometers are increasingly incorporating photonic technologies due to the increase in fidelity of the data generated. Here, we report the design, construction and commissioning of a new high‐contrast imager, the integrated pupil‐remapping interferometer, an instrument we expect will find application in the detection of young faint companions in the nearest star‐forming regions. The laboratory characterization of the instrument demonstrated high‐visibility fringes on all interferometer baselines in addition to stable closure phase signals. We also report the first successful on‐sky experiments with the prototype instrument at the 3.9‐m Anglo‐Australian Telescope. Performance metrics recovered were consistent with ideal device behaviour after accounting for expected levels of decoherence and signal loss from the uncompensated seeing. The prospect of complete Fourier coverage coupled with the current performance metrics means that this photonically enhanced instrument is well positioned to contribute to the science of high‐contrast companions.
The CLAS12 Spectrometer at Jefferson Laboratory Adhikari, S.; Amaryan, M.J.; Angelini, G. ...
Nuclear instruments & methods in physics research. Section A, Accelerators, spectrometers, detectors and associated equipment,
04/2020, Letnik:
959, Številka:
C
Journal Article
Recenzirano
Odprti dostop
The CEBAF Large Acceptance Spectrometer for operation at 12 GeV beam energy (CLAS12) in Hall B at Jefferson Laboratory is used to study electro-induced nuclear and hadronic reactions. This ...spectrometer provides efficient detection of charged and neutral particles over a large fraction of the full solid angle. CLAS12 has been part of the energy-doubling project of Jefferson Lab’s Continuous Electron Beam Accelerator Facility, funded by the United States Department of Energy. An international collaboration of 48 institutions contributed to the design and construction of detector hardware, developed the software packages for the simulation of complex event patterns, and commissioned the detector systems. CLAS12 is based on a dual-magnet system with a superconducting torus magnet that provides a largely azimuthal field distribution that covers the forward polar angle range up to 35∘, and a solenoid magnet and detector covering the polar angles from 35° to 125° with full azimuthal coverage. Trajectory reconstruction in the forward direction using drift chambers and in the central direction using a vertex tracker results in momentum resolutions of <1% and <3%, respectively. Cherenkov counters, time-of-flight scintillators, and electromagnetic calorimeters provide good particle identification. Fast triggering and high data-acquisition rates allow operation at a luminosity of 1035 cm−2s−1. These capabilities are being used in a broad program to study the structure and interactions of nucleons, nuclei, and mesons, using polarized and unpolarized electron beams and targets for beam energies up to 11 GeV. This paper gives a general description of the design, construction, and performance of CLAS12.
Background
Patients undergoing prolonged pelvic surgery may develop compartment syndrome of one or both lower limbs in the absence of direct trauma or pre‐existing vascular disease (well leg ...compartment syndrome). This condition may have devastating consequences for postoperative recovery, including loss of life or limb, and irreversible disability.
Methods
These guidelines represent the collaboration of a multidisciplinary group of colorectal, vascular and orthopaedic surgeons, acting on behalf of their specialty associations in the UK and Ireland. A systematic analysis of the available peer‐reviewed literature was undertaken to provide an evidence base from which these guidelines were developed.
Results
These guidelines encompass the risk factors (both patient‐ and procedure‐related), diagnosis and management of the condition. Key recommendations for the adoption of perioperative strategies to facilitate prevention and effective treatment of well leg compartment syndrome are presented.
Conclusion
All surgeons who carry out abdominopelvic surgical procedures should be aware of well leg compartment syndrome, and instigate policies within their own institution to reduce the risk of this potentially life‐changing complication.
This article reviews the published literature relating to the aetiology, pathophysiology, clinical features, diagnosis and management of lower limb compartment syndrome after pelvic surgery. Guidelines on prevention, diagnosis and management, endorsed by the relevant surgical specialty associations, are presented.
Rare, but preventable
We present the main findings of the 5th National Audit Project (NAP5) on accidental awareness during general anaesthesia (AAGA). Incidences were estimated using reports of accidental awareness as the ...numerator, and a parallel national anaesthetic activity survey to provide denominator data. The incidence of certain/probable and possible accidental awareness cases was ∼1:19 600 anaesthetics (95% confidence interval 1:16 700–23 450). However, there was considerable variation across subtypes of techniques or subspecialities. The incidence with neuromuscular block (NMB) was ∼1:8200 (1:7030–9700), and without, it was ∼1:135 900 (1:78 600–299 000). The cases of AAGA reported to NAP5 were overwhelmingly cases of unintended awareness during NMB. The incidence of accidental awareness during Caesarean section was ∼1:670 (1:380–1300). Two-thirds (82, 66%) of cases of accidental awareness experiences arose in the dynamic phases of anaesthesia, namely induction of and emergence from anaesthesia. During induction of anaesthesia, contributory factors included: use of thiopental, rapid sequence induction, obesity, difficult airway management, NMB, and interruptions of anaesthetic delivery during movement from anaesthetic room to theatre. During emergence from anaesthesia, residual paralysis was perceived by patients as accidental awareness, and commonly related to a failure to ensure full return of motor capacity. One-third (43, 33%) of accidental awareness events arose during the maintenance phase of anaesthesia, mostly due to problems at induction or towards the end of anaesthesia. Factors increasing the risk of accidental awareness included: female sex, age (younger adults, but not children), obesity, anaesthetist seniority (junior trainees), previous awareness, out-of-hours operating, emergencies, type of surgery (obstetric, cardiac, thoracic), and use of NMB. The following factors were not risk factors for accidental awareness: ASA physical status, race, and use or omission of nitrous oxide. We recommend that an anaesthetic checklist, to be an integral part of the World Health Organization Safer Surgery checklist, is introduced as an aid to preventing accidental awareness. This paper is a shortened version describing the main findings from NAP5—the full report can be found at http://www.nationalauditprojects.org.uk/NAP5_home.
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