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1.
Can Geriatr J ; 25(4): 375-379, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36505914

RESUMO

Background: Characterizing the prevalence and distribution of frailty within a population can help guide decision-making and policy development by identifying health service resource needs. Here we describe the prevalence of frailty among hospitalized older adults in New Brunswick (NB), Canada. Methods: NB administrative hospital claims data were used to identify hospitalized older adults aged 65 or older between April 1, 2017 and March 31, 2019. Frailty was quantified using the Hospital Frailty Risk Score (HFRS), a validated frailty tool derived from claims data. Individuals with a HFRS ranked as intermediate or high were categorized as frail. The distribution of frailty across sex and age are described. Crude prevalence estimates and corresponding 95% confidence intervals are presented. Results: A total of 55,675 older adults (52% females) were hospitalized. The overall prevalence of frailty was 21.2% (95%CI: 20.9-21.6). Prevalence increased with age: 12.7% (95%CI: 12.3-13.1) in the 65-74 age group, 24.7% (95%CI: 24.1-25.3) in the 75-84 age group and 41.6% (95%CI: 40.6-42.7) for those aged 85 and over (p<.001). Discussion/Conclusion: The distribution of frailty is in line with that reported in other jurisdictions. We demonstrate the feasibility of the HFRS to identify and characterize frailty in a large sample of older adults who were hospitalized, using administrative data.

2.
Artigo em Inglês | MEDLINE | ID: mdl-35742507

RESUMO

In the early 2000s, the Province of New Brunswick, Canada, undertook health system restructuring, including closing some rural hospitals. We examined whether changes in geographic access to hospitals and primary care were associated with changes in patterns of hospital use. We described three measures of hospital use for ambulatory care sensitive conditions (ACSCs) among adults 75 years and younger annually during the period 2004-2013 overall, and at the community scale. We described spatial and temporal patterns in: age-standardized hospitalization rates, age-standardized incidence of hospital admissions, and rates of admissions via ambulance. Overall, rates and incidence of hospitalizations for ACSCs declined while admissions via ambulance remained largely unchanged. We observed considerable regional variation in rates between communities in 2004. This regional variation decreased over time, with rural areas demonstrating the sharpest declines. Changes in hospital service provision within individual communities had little impact on rates of ACSC admissions. Results were consistent across urban and rural communities and were robust to analyses that included older patients and those admitted for reasons other than ACSCs. Our results suggest that the restructuring and hospital closures did not result in substantial changes to regional patterns or rates of service use.


Assuntos
Assistência Ambulatorial , Hospitais Rurais , Adulto , Fechamento de Instituições de Saúde , Hospitalização , Humanos , Novo Brunswick/epidemiologia , População Rural
3.
Opt Express ; 30(5): 7383-7393, 2022 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-35299502

RESUMO

Extreme lasers capable of short, high-energy pulses are probing the frontiers of science and advancing practical technology. The utility of such lasers increases with their average power delivery, which enables faster data acquisition, higher flux of laser-driven particle and radiation sources and more efficient material processing. However, the same extreme energies and electric field strengths of these lasers are currently preventing their direct and high accuracy measurement for these experimental applications. To overcome this limitation, we use the momentum of the laser pulses as a measurement proxy for their energy. When light reflects from an ideal mirror, its momentum is transferred to the mirror, but its energy is reflected. We demonstrate here a force-sensing mirror configuration to measure laser pulse energies up to 100 J/pulse (10 ns duration, 10 Hz repetition rate) from a kilowatt-level average power multi-slab laser operated at the HiLASE facility of the Czech Academy of Sciences. We combine a radiation-pressure power meter with a charge integrator photodiode to form what we refer to as a Radiation Pressure Energy Meter. To our knowledge, this is the first demonstration of a high-accuracy, non-absorbing, SI traceable primary standard measurement of both single and average pulse energies of a 1-kW-average-power pulsed laser source. With this, we demonstrate a practical method for in-situ calibration of the traditional thermal instruments (pyroelectric detectors) currently used for indirect measurements of energy and power of such extreme lasers.

4.
Metrologia ; 58(5)2021.
Artigo em Inglês | MEDLINE | ID: mdl-36733973

RESUMO

We present the first measurements of kilowatt laser power with an uncertainty less than 1 %. These represent progress toward the most accurate measurements of laser power above 1 kW at 1070 nm wavelength and establish a more precise link between force metrology and laser power metrology. Radiation pressure, or photon momentum, is a relatively new method of non-destructively measuring laser power. We demonstrate how a multiple reflection optical system amplifies the pressure of a kilowatt class laser incoherently to improve the signal to noise ratio in a radiation pressure-based measurement. With 14 incoherent reflections of the laser, we measure a total uncertainty of 0.26 % for an input power of 10 kW and 0.46 % for an input power of 1 kW at the 95 % confidence level. These measurements of absolute power are traceable to the SI kilogram and mark a state-of-the-art improvement in measurement precision by a factor of four.

5.
Appl Opt ; 59(28): 8719-8723, 2020 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-33104554

RESUMO

Photon momentum radiometers measure the force imparted by a reflected laser beam to determine the laser's optical power. This requires high-accuracy calibration of the force sensors using milligram and microgram mass artifacts. Calibrated test masses can therefore be used to provide traceability of these radiometers to the International System of Units, but low-noise calibration at these mass levels is difficult. Here, we present the improvement in calibration capability that we have gained from implementing a robotic mass delivery system. We quantify this in terms of the specific nuances of force measurements as implemented for laser power metrology.

7.
Appl Opt ; 58(5): 1239-1241, 2019 Feb 10.
Artigo em Inglês | MEDLINE | ID: mdl-30873992

RESUMO

We present a novel measurement scheme and instrumentation for quantifying laser power by means of photon momentum. The optical design is optimized such that the incoming laser beam is minimally perturbed and is available for other purposes along the incoming beam axis. Additionally, the geometry of the instrument gives access to the small but measurable transmittance between two passive mirrors that face the force sensor. The force sensor is based on a commercially available weighing instrument ("scale") that has a temporal response of approximately 5 s and a readability of approximately 1 µg (∼2 W). Our measurement results demonstrate beam profile and power for 500 W, but the mirror and mass (or force) calibration are suitable for very high power up to 50 kW and beyond. The optics are based on commercially available, off-the-shelf mirrors optimized for the angle of incidence and maximum reflectance at the wavelength of 1070 nm. The size of the complete instrument has an input aperture of Ø75 mm, but this constraint is only a matter of optimizing the beam path and box geometry.

8.
Opt Express ; 25(4): 4382-4392, 2017 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-28241641

RESUMO

We describe a non-traditional optical power meter which measures radiation pressure to accurately determine a laser's optical power output. This approach traces its calibration of the optical watt to the kilogram. Our power meter is designed for high-accuracy and portability with the capability of multi-kilowatt measurements whose upper power limit is constrained only by the mirror quality. We provide detailed uncertainty evaluation and validate experimentally an average expanded relative uncertainty of 0.016 from 1 kW to 10 kW. Radiation pressure as a power measurement tool is unique to the extent that it does not rely on absorption of the light to produce a high-accuracy result. This permits fast measurements, simplifies power scalability, and allows high-accuracy measurements to be made during use of the laser for other applications.

9.
ChemSusChem ; 9(14): 1750-72, 2016 07 21.
Artigo em Inglês | MEDLINE | ID: mdl-27385663

RESUMO

Research development of processes for refining bio-oils is becoming increasingly popular. One issue that these processes possess is their high requirement for H2 gas. In response, researchers must develop catalysts that perform deoxygenation while minimizing H2 consumption-selective deoxygenation. Unlike traditional deoxygenation processes, selective deoxygenation reactions and catalysts represent an information gap that, prior to this publication, has yet to be reviewed. This review addresses the gap by providing both a summary of recent research developments and insight into future developments of new catalytic materials. Bifunctional catalysts containing a combination of oxophilicity and an active metal phase appear to be the most beneficial for selective deoxygenation processes in a H2 -modest environment. It is important that catalysts have a supply of disassociated hydrogen, because without such, activity and stability will suffer. The authors recommend to maximize the use of internally available hydrogen in bio-fuel, which may be the only viable approach for deoxygenation if external H2 gas is limited. This would be possible through the development of catalysts that promote both the water-gas-shift and deoxygenation reactions.


Assuntos
Biocombustíveis , Biomassa , Hidrogênio/química , Óleos de Plantas/química , Catálise
10.
Int J Clin Exp Pathol ; 6(11): 2419-29, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-24228104

RESUMO

Human aldo-keto reductase family 1 member C3 (AKR1C3) was initially identified as an enzyme in reducing 5α-dihydrotestosterone (5α-DHT) to 5α-androstane-3α, 17ß-diol (3α-diol) and oxidizing 3α-diol to androsterone. It was subsequently demonstrated to possess ketosteroid reductase activity in metabolizing other steroids including estrogen and progesterone, 11-ketoprostaglandin reductase activity in metabolizing prostaglandins, and dihydrodiol dehydrogenase x (DDx) activity in metabolizing xenobiotics. AKR1C3 was demonstrated in sex hormone-dependent tissues including testis, breast, endometrium, and prostate; in sex hormone-independent tissues including kidney and urothelium. Our previous study described the expression of AKR1C3 in squamous cell carcinoma and adenocarcinoma but not in small cell carcinoma. In this report, we studied the expression of AKR1C3 in normal tissue, adenocarcinomas (43 cases) and neuroendocrine (NE) tumors (40 cases) arising from the aerodigestive tract and pancreas. We demonstrated wide expression of AKR1C3 in superficially located mucosal cells, but not in NE cells. AKR1C3-positive immunoreactivity was detected in 38 cases (88.4%) of adenocarcinoma, but only in 7 cases (17.5%) of NE tumors in all cases. All NE tumors arising from the pancreas and appendix and most tumors from the colon and lung were negative. The highest ratio of positive AKR1C3 in NE tumors was found in tumors arising from the small intestine (50%). These results raise the question of AKR1C3's role in the biology of normal mucosal epithelia and tumors. In addition, AKR1C3 may be a useful adjunct marker for the exclusion of the NE phenotype in diagnostic pathology.


Assuntos
3-Hidroxiesteroide Desidrogenases/análise , Adenocarcinoma/enzimologia , Biomarcadores Tumorais/análise , Neoplasias Gastrointestinais/enzimologia , Hidroxiprostaglandina Desidrogenases/análise , Neoplasias Pulmonares/enzimologia , Tumores Neuroendócrinos/enzimologia , Neoplasias Pancreáticas/enzimologia , Adenocarcinoma/patologia , Membro C3 da Família 1 de alfa-Ceto Redutase , Neoplasias Gastrointestinais/patologia , Humanos , Imuno-Histoquímica , Neoplasias Pulmonares/patologia , Tumores Neuroendócrinos/patologia , Neoplasias Pancreáticas/patologia , Prognóstico
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