89 research outputs found
On-Chip Cavity Optomechanical Coupling
On-chip cavity optomechanics, in which strong co-localization of light and
mechanical motion is engineered, relies on efficient coupling of light both
into and out of the on-chip optical resonator. Here we detail our particular
style of tapered and dimpled optical fibers, pioneered by the Painter group at
Caltech, which are a versatile and reliable solution to efficient on-chip
coupling. First, a brief overview of tapered, single mode fibers is presented,
in which the single mode cutoff diameter is highlighted. The apparatus used to
create a dimpled tapered fiber is then described, followed by a comprehensive
account of the procedure by which a dimpled tapered fiber is produced and
mounted in our system. The custom-built optical access vacuum chambers in which
our on-chip optomechanical measurements are performed are then discussed.
Finally, the process by which our optomechanical devices are fabricated and the
method by which we explore their optical and mechanical properties is
explained. It is our expectation that this manuscript will enable the novice to
develop advanced optomechanical experiments.Comment: 31 pages, 9 figure
Faecal haemoglobin and faecal calprotectin as indicators of bowel disease in patients presenting to primary care with bowel symptoms
OBJECTIVE: In primary care, assessing which patients with bowel symptoms harbour significant disease (cancer, higher-risk adenoma or IBD) is difficult. We studied the diagnostic accuracies of faecal haemoglobin (FHb) and faecal calprotectin (FC) in a cohort of symptomatic patients. DESIGN: From October 2013 to March 2014, general practitioners were prompted to request FHb and FC when referring patients with bowel symptoms to secondary care. Faecal samples were analysed for haemoglobin (EIKEN OC-Sensor io) and calprotectin (BĂHLMANN Calprotectin ELISA). Patients triaged to endoscopy were investigated within 6â
weeks. All clinicians and endoscopists were blind to the faecal test results. The diagnostic accuracies of FHb and FC for identification of significant bowel disease were assessed. RESULTS: 1043 patients returned samples. FHb was detectable in 57.6% (median 0.4â
”g/g, 95% CI 0.4 to 0.8; range 0â200). FC at 50â
”g/g or above was present in 60.0%. 755 patients (54.6% women, median age 64â
years (range 16â90, IQR 52â73)) returned samples and completed colonic investigations. 103 patients had significant bowel disease; the negative predictive values of FHb for colorectal cancer, higher-risk adenoma and IBD were 100%, 97.8% and 98.4%, respectively. Using cut-offs of detectable FHb and/or 200â
”g/g FC detected two further cases of IBD, one higher-risk adenoma and no additional cancers. CONCLUSIONS: In primary care, undetectable FHb is a good ârule-outâ test for significant bowel disease and could guide who requires investigation
Population screening for colorectal cancer means getting FIT:the past, present, and future of colorectal cancer screening using the fecal immunochemical test for hemoglobin (FIT)
Fecal immunochemical tests for hemoglobin (FIT) are changing the manner in which colorectal cancer (CRC) is screened. Although these tests are being performed worldwide, why is this test different from its predecessors? What evidence supports its adoption? How can this evidence best be used? This review addresses these questions and provides an understanding of FIT theory and practices to expedite international efforts to implement the use of FIT in CRC screening
Faecal immunochemical tests for haemoglobin (FIT) in the assessment of patients with lower abdominal symptoms:current controversies
Internet use for family carers of people with intellectual disabilities: A literature review and thematic synthesis
Being a family carer can be rewarding but can also lead to mental and physical exhaustion as well as feelings of social exclusion and isolation. Research has shown that the use of the Internet and online forums can provide an immediate place to find information and reassurance and that forum use can be an empathetic place to share experiences and seek emotional support. This article details a systematic literature search of research on carers of people with intellectual disabilities and/or autism using the Internet. A thematic synthesis of the resulting papers identified that online forums give carers a sense of agency by providing a place to go for informational support that may not be elsewhere. Carers also enjoyed the safe community of solidarity and emotional support that online forums provide. An important finding is the lack of published papers in this area with the inclusion of just eight papers
Reply to: Concerns about estimating relative risk of death associated with convalescent plasma for COVID-19
Author Correction: Convalescent plasma for hospitalized patients with COVID-19: an open-label, randomized controlled trial (Nature Medicine, (2021), 27, 11, (2012-2024), 10.1038/s41591-021-01488-2)
In the version of this Article initially published, there was an omission in the member list for the CONCOR-1 Study Group. Valérie Arsenault (Héma-Québec, Montreal, Quebec, Canada) has now been included in the CONCOR-1 Study Group in the online version of the article
Gemini Observations of Galaxies in Rich Early Environments (GOGREEN) I : survey description
We describe a new Large Program in progress on the Gemini North and South telescopes: Gemini Observations of Galaxies in Rich Early Environments (GOGREEN). This is an imaging and deep spectroscopic survey of 21 galaxy systems at 1 10 in halo mass. The scientific objectives include measuring the role of environment in the evolution of low-mass galaxies, and measuring the dynamics and stellar contents of their host haloes. The targets are selected from the SpARCS, SPT, COSMOS, and SXDS surveys, to be the evolutionary counterparts of today's clusters and groups. The new red-sensitive Hamamatsu detectors on GMOS, coupled with the nod-and-shuffle sky subtraction, allow simultaneous wavelength coverage over lambda similar to 0.6-1.05 mu m, and this enables a homogeneous and statistically complete redshift survey of galaxies of all types. The spectroscopic sample targets galaxies with AB magnitudes z' <24.25 and [3.6] mu m <22.5, and is therefore statistically complete for stellar masses M* greater than or similar to 10(10.3) M-circle dot, for all galaxy types and over the entire redshift range. Deep, multiwavelength imaging has been acquired over larger fields for most systems, spanning u through K, in addition to deep IRAC imaging at 3.6 mu m. The spectroscopy is similar to 50 per cent complete as of semester 17A, and we anticipate a final sample of similar to 500 new cluster members. Combined with existing spectroscopy on the brighter galaxies from GCLASS, SPT, and other sources, GOGREEN will be a large legacy cluster and field galaxy sample at this redshift that spectroscopically covers a wide range in stellar mass, halo mass, and clustercentric radius.Peer reviewe
The pathophysiology of fluid and electrolyte balance in the older adult surgical patient
Background & aims:
Age-related physiological changes predispose even the healthy older adult to fluid and electrolyte abnormalities which can cause morbidity and mortality. The aim of this narrative review is to highlight key aspects of age-related pathophysiological changes that affect fluid and electrolyte
balance in older adults and underpin their importance in the perioperative period.
Methods:
The Web of Science, MEDLINE, PubMed and Google Scholar databases were searched using key terms for relevant studies published in English on fluid balance in older adults during the 15 years preceding June 2013. Randomised controlled trials and large cohort studies were sought; other studieswere used when these were not available. The bibliographies of extracted papers were also searched for relevant articles.
Results:
Older adults are susceptible to dehydration and electrolyte abnormalities, with causes ranging from physical disability restricting access to fluid intake to iatrogenic causes including polypharmacy and unmonitored diuretic usage. Renal senescence, as well as physical and mental decline, increase this susceptibility. Older adults are also predisposed to water retention and related electrolyte abnormalities, exacerbated at times of physiological stress. Positive fluid balance has been shown to be an independent risk factor for morbidity and mortality in critically ill patients with acute kidney injury.
Conclusions: Age-related pathophysiological changes in the handling of fluid and electrolytes make older adults undergoing surgery a high-risk group and an understanding of these changes will enable better management of fluid and electrolyte therapy in the older adult
Core Outcome Set for Research and Clinical Practice in Post COVID-19 Condition (Long COVID): An International Delphi Consensus Study âPC-COSâ
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