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1.
Rev Sci Instrum ; 94(5)2023 May 01.
Article in English | MEDLINE | ID: mdl-37171234

ABSTRACT

The Oak Ridge National Laboratory is planning to build the Second Target Station (STS) at the Spallation Neutron Source (SNS). STS will host a suite of novel instruments that complement the First Target Station's beamline capabilities by offering an increased flux for cold neutrons and a broader wavelength bandwidth. A novel neutron imaging beamline, named the Complex, Unique, and Powerful Imaging Instrument for Dynamics (CUPI2D), is among the first eight instruments that will be commissioned at STS as part of the construction project. CUPI2D is designed for a broad range of neutron imaging scientific applications, such as energy storage and conversion (batteries and fuel cells), materials science and engineering (additive manufacturing, superalloys, and archaeometry), nuclear materials (novel cladding materials, nuclear fuel, and moderators), cementitious materials, biology/medical/dental applications (regenerative medicine and cancer), and life sciences (plant-soil interactions and nutrient dynamics). The innovation of this instrument lies in the utilization of a high flux of wavelength-separated cold neutrons to perform real time in situ neutron grating interferometry and Bragg edge imaging-with a wavelength resolution of δλ/λ ≈ 0.3%-simultaneously when required, across a broad range of length and time scales. This manuscript briefly describes the science enabled at CUPI2D based on its unique capabilities. The preliminary beamline performance, a design concept, and future development requirements are also presented.

2.
J Imaging ; 8(7)2022 Jul 18.
Article in English | MEDLINE | ID: mdl-35877645

ABSTRACT

The high penetration depth of neutrons through many metals and other common materials makes neutron imaging an attractive method for non-destructively probing the internal structure and dynamics of objects or systems that may not be accessible by conventional means, such as X-ray or optical imaging. While neutron imaging has been demonstrated to achieve a spatial resolution below 10 µm and temporal resolution below 10 µs, the relatively low flux of neutron sources and the limitations of existing neutron detectors have, until now, dictated that these cannot be achieved simultaneously, which substantially restricts the applicability of neutron imaging to many fields of research that could otherwise benefit from its unique capabilities. In this work, we present an attenuation modeling approach to the quantification of sub-pixel dynamics in cyclic ensemble neutron image sequences of an automotive gasoline direct injector at a 5 µs time scale with a spatial noise floor in the order of 5 µm.

4.
Am J Gastroenterol ; 117(2): 301-310, 2022 02 01.
Article in English | MEDLINE | ID: mdl-34962498

ABSTRACT

INTRODUCTION: Several scoring systems predict mortality in alcohol-associated hepatitis (AH), including the Maddrey discriminant function (mDF) and model for end-stage liver disease (MELD) score developed in the United States, Glasgow alcoholic hepatitis score in the United Kingdom, and age, bilirubin, international normalized ratio, and creatinine score in Spain. To date, no global studies have examined the utility of these scores, nor has the MELD-sodium been evaluated for outcome prediction in AH. In this study, we assessed the accuracy of different scores to predict short-term mortality in AH and investigated additional factors to improve mortality prediction. METHODS: Patients admitted to hospital with a definite or probable AH were recruited by 85 tertiary centers in 11 countries and across 3 continents. Baseline demographic and laboratory variables were obtained. The primary outcome was all-cause mortality at 28 and 90 days. RESULTS: In total, 3,101 patients were eligible for inclusion. After exclusions (n = 520), 2,581 patients were enrolled (74.4% male, median age 48 years, interquartile range 40.9-55.0 years). The median MELD score was 23.5 (interquartile range 20.5-27.8). Mortality at 28 and 90 days was 20% and 30.9%, respectively. The area under the receiver operating characteristic curve for 28-day mortality ranged from 0.776 for MELD-sodium to 0.701 for mDF, and for 90-day mortality, it ranged from 0.773 for MELD to 0.709 for mDF. The area under the receiver operating characteristic curve for mDF to predict death was significantly lower than all other scores. Age added to MELD obtained only a small improvement of AUC. DISCUSSION: These results suggest that the mDF score should no longer be used to assess AH's prognosis. The MELD score has the best performance in predicting short-term mortality.


Subject(s)
End Stage Liver Disease/etiology , Hepatitis, Alcoholic/mortality , Liver/physiopathology , Adult , Discriminant Analysis , End Stage Liver Disease/mortality , End Stage Liver Disease/physiopathology , Female , Follow-Up Studies , Global Health , Hepatitis, Alcoholic/complications , Hepatitis, Alcoholic/physiopathology , Humans , Liver Function Tests , Male , Middle Aged , Prognosis , ROC Curve , Risk Factors , Severity of Illness Index , Survival Rate/trends , Time Factors
5.
CJEM ; 19(4): 317-320, 2017 Jul.
Article in English | MEDLINE | ID: mdl-27573473

ABSTRACT

Point of care ultrasound in the emergency department (ED) is increasingly being used to diagnose time-sensitive, vision-threatening conditions. We present a case of a 64-year-old female who presented to the ED with a three-day history of worsening left eye floaters. Point of care ocular ultrasound demonstrated a posterior chamber containing many echogenic opacities of varying size without acoustic shadowing. Movement of the eye resulted in significant after-movement of these opacities, giving the classic "washing machine" appearance seen with vitreous hemorrhage (VH). Based on these ultrasound findings, the patient was diagnosed with a VH and was referred to ophthalmology. The consulting ophthalmologist ultimately diagnosed the patient with asteroid hyalosis without VH. Asteroid hyalosis is a benign condition of the vitreous resulting in calcium phosphate and lipid deposits that can mimic more serious VH on point of care ultrasound. Knowledge of this mimic is helpful for communication with specialists and for awareness of the potential for misdiagnosis with ocular ultrasound.


Subject(s)
Eye Diseases/diagnostic imaging , Point-of-Care Systems , Ultrasonography/methods , Vitreous Body , Diagnosis, Differential , Emergency Service, Hospital , Female , Humans , Middle Aged , Vitreous Hemorrhage/diagnostic imaging
6.
Niger J Med ; 21(3): 308-12, 2012.
Article in English | MEDLINE | ID: mdl-23304926

ABSTRACT

BACKGROUND: Fractures of the zygomatic complex occur worldwide and are a component part of injuries that can be sustained in the maxillofacial region. The objective was to analyze the clinical presentation and management ofzygomatic complex fractures. METHODS: This was a prospective study carried out over a period of five years at the University of Calabar Teaching Hospital, Nigeria. Data documented were patients' age, gender, time of presentation, cause and type of fracture, associated head and maxillofacial injuries, clinical features, types of plain radiographs, treatment methods, duration of follow-up and complications. RESULTS: Majority of the patients (n = 81, 63.3%) were in their third and fourth decades of life while the male to female ratio was 20.3:1. Road traffic accident (n = 111, 86.7%) was the most common cause of fracture. Fractures of the zygomatic complex alone (n = 105, 82.0%) were more common than isolated fractures of the arch (n = 13, 10.2%) and combined fractures of the zygomatic complex and arch (n = 10, 7.8%). CONCLUSION: While multi-disciplinary approach to treatment is important, majority of the fractures were treated by simple elevation and transosseous wire osteosynthesis. Delay in presentation, associated injuries and non-availability of mini-plating technique contributed to the development of complications.


Subject(s)
Fracture Fixation, Internal , Fractures, Comminuted/surgery , Zygomatic Fractures/surgery , Accidents, Traffic , Adolescent , Adult , Aged , Aged, 80 and over , Child , Female , Fractures, Comminuted/diagnosis , Fractures, Comminuted/etiology , Hospitals, Teaching , Humans , Male , Middle Aged , Nigeria , Prospective Studies , Young Adult , Zygomatic Fractures/diagnosis , Zygomatic Fractures/etiology
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