scholarly journals Low Dose Chest CT and Lung Ultrasound for the Diagnosis and Management of COVID-19

2021 ◽  
Vol 10 (10) ◽  
pp. 2196
Author(s):  
Julie Finance ◽  
Laurent Zieleskewicz ◽  
Paul Habert ◽  
Alexis Jacquier ◽  
Philippe Parola ◽  
...  
Keyword(s):  
Infectious Disease ◽  
Large Scale ◽  
Low Dose ◽  
Lung Ultrasound ◽  
Imaging Techniques ◽  
Infectious Disease Specialists ◽  
Patient Prognosis ◽  
Low Dose Computed Tomography ◽  
Dose Imaging

Background: The COVID-19 pandemic has provided an opportunity to use low- and non-radiating chest imaging techniques on a large scale in the context of an infectious disease, which has never been done before. Previously, low-dose techniques were rarely used for infectious diseases, despite the recognised danger of ionising radiation. Method: To evaluate the role of low-dose computed tomography (LDCT) and lung ultrasound (LUS) in managing COVID-19 pneumonia, we performed a review of the literature including our cases. Results: Chest LDCT is now performed routinely when diagnosing and assessing the severity of COVID-19, allowing patients to be rapidly triaged. The extent of lung involvement assessed by LDCT is accurate in terms of predicting poor clinical outcomes in COVID-19-infected patients. Infectious disease specialists are less familiar with LUS, but this technique is also of great interest for a rapid diagnosis of patients with COVID-19 and is effective at assessing patient prognosis. Conclusions: COVID-19 is currently accelerating the transition to low-dose and “no-dose” imaging techniques to explore infectious pneumonia and their long-term consequences.

Quantitative nano-characterization of heterogeneous catalysts

1995 ◽  
Vol 53 ◽  
pp. 398-399
Author(s):  
P.A. Crozier ◽  
M. Pan
Keyword(s):  
Heterogeneous Catalysts ◽  
Low Dose ◽  
Imaging Techniques ◽  
Structural Features ◽  
Catalyst Characterization ◽  
New Developments ◽  
Double Phase ◽  
Phase Systems ◽  
Dose Imaging

Heterogeneous catalysts can be of varying complexity ranging from single or double phase systems to complicated mixtures of metals and oxides with additives to help promote chemical reactions, extend the life of the catalysts, prevent poisoning etc. Although catalysis occurs on the surface of most systems, detailed descriptions of the microstructure and chemistry of catalysts can be helpful for developing an understanding of the mechanism by which a catalyst facilitates a reaction. Recent years have seen continued development and improvement of various TEM, STEM and AEM techniques for yielding information on the structure and chemistry of catalysts on the nanometer scale. Here we review some quantitative approaches to catalyst characterization that have resulted from new developments in instrumentation.HREM has been used to examine structural features of catalysts often by employing profile imaging techniques to study atomic details on the surface. Digital recording techniques employing slow-scan CCD cameras have facilitated the use of low-dose imaging in zeolite structure analysis and electron crystallography. Fig. la shows a low-dose image from SSZ-33 zeolite revealing the presence of a stacking fault.

BACKGROUND RADIATION LEVELS NEAR A MINERAL SAND MINING FACTORY IN SRI LANKA: CORRELATION OF RADIATION MEASUREMENTS WITH MICRONUCLEI FREQUENCY

2020 ◽  
Vol 189 (1) ◽  
pp. 114-126 ◽  
Author(s):  
Tania Warnakulasuriya ◽  
Senani Williams ◽  
Thiwanka Weerakkody ◽  
Mangala Dabarera ◽  
Kusum Rodrigo ◽  
...  
Keyword(s):  
Sri Lanka ◽  
Large Scale ◽  
Low Dose ◽  
Background Radiation ◽  
Venous Blood ◽  
Low Dose Radiation ◽  
Cross Sectional ◽  
Radiation Measurements ◽  
Dose Radiation

Abstract Lanka Mineral Sands Ltd (LMS) is a company operating in Pulmoddai, Sri Lanka, mining for rare earth minerals along with monazite which contains thorium that emits ionizing gamma and alpha radiation on decay. The objective of the study was to determine the background radiation levels and selected radionuclides and then to correlate these levels with the frequency of micronuclei (MN) among persons residing in the vicinity of LMS. A cross-sectional study was conducted among persons of both sexes between 35 and 45 years of age residing in the vicinity of LMS. Background radiation measurements were obtained by a survey metre, and gamma spectrometry was done on soil samples. Five millilitres of venous blood was drawn for cytokinesis-blocked MN assay. Background radiation levels measured by the survey metre; 232Th, 226Ra and 210Pb mass activities in soil were highest in the samples collected from the LMS. The background radiation measurements positively correlated with MN frequency although the magnitude of the correlation was small (r = 0.176, p = 0.04). This implies that chronic long-term exposure to low-dose radiation may result in genotoxicity. Prospective large-scale studies are recommended to evaluate the long-term effect of exposure to low-dose radiation at Pulmoddai.

Comparing mortality of colorectal cancer and gastrointestinal bleeding among patients with long-term use of low dose aspirin: A population-based study of 689,209 patients.

2017 ◽  
Vol 35 (4_suppl) ◽  
pp. 527-527
Author(s):  
Joseph Sung ◽  
Kelvin Kf Tsoi
Keyword(s):  
Colorectal Cancer ◽  
Gastrointestinal Bleeding ◽  
Large Scale ◽  
Low Dose ◽  
Population Based ◽  
Dose Aspirin ◽  
Increased Risk ◽  
Incidence And Mortality ◽  
Low Dose Aspirin

527 Background: Aspirin, commonly used for prevention of cardiovascular and cerebrovascular diseases, is well-known to protect against colorectal cancer (CRC) development but increase risk of gastrointestinal bleeding (GIB). Few large-scale studies have compared the benefit and risk of long-term aspirin usage. This cohort study aims to evaluate the use of low-dose aspirin to prevent CRC and the risk of GIB associated with the aspirin use. Methods: A population-based clinical dataset was used to compare incidence and mortality of CRC and GIB patients receiving low-dose aspirin with sex-and-age matched controls (in 1:2 ratio). Patients with aspirin≤6 months were excluded. Clinical data of 206,243 aspirin users (mean dose 80 mg/day, mean duration 7.7 years) and 482,966 non-users were included. All patients must have at least 10-year follow up on clinical outcome. Results: Among aspirin users 5,776 (2.80%) were diagnosed with CRC; 2,097 (1.02%) died of the malignancy. 16,483 (3.41%) non-users were diagnosed with CRC; 7,963 (1.65%) died of CRC. Using the cox-proportional hazard regression, aspirin usage showed a modest but significant reduction in CRC mortality (HR = 0.65; 95% CI = 0.62 to 0.69). On the other hand, 11,187 (5.42%) aspirin users developed GIB, and 841 (0.41%) died. 15,186 (3.14%) non-users developed GIB, and 1,682 patients (0.35%) died. Aspirin users showed modest but significant increased risk of GIB-related mortality (HR = 1.24; 95% CI = 1.14 to 1.35). Conclusions: The long-term use of low dose aspirin shows preventive effect on CRC, but also increases the associated GIB risk. Considerations of prophylactic use of aspirin should balance the benefit and the risk of this treatment to the target population. [Table: see text]

scholarly journals Whole-Body Low-Dose Computed Tomography and Advanced Imaging Techniques for Multiple Myeloma Bone Disease

2014 ◽  
Vol 20 (23) ◽  
pp. 5888-5897 ◽  
Author(s):  
Matthew J. Pianko ◽  
Evangelos Terpos ◽  
G. David Roodman ◽  
Chaitanya R. Divgi ◽  
Sonja Zweegman ◽  
...  
Keyword(s):  
Computed Tomography ◽  
Multiple Myeloma ◽  
Bone Disease ◽  
Low Dose ◽  
Imaging Techniques ◽  
Whole Body ◽  
Advanced Imaging ◽  
Myeloma Bone Disease ◽  
Low Dose Computed Tomography

scholarly journals Outcomes of Long-term Interval Rescreening With Low-Dose Computed Tomography for Lung Cancer in Different Risk Cohorts

2019 ◽  
Vol 14 (6) ◽  
pp. 1003-1011 ◽  
Author(s):  
Reenika Aggarwal ◽  
Andrew C.L. Lam ◽  
Maureen McGregor ◽  
Ravi Menezes ◽  
Katrina Hueniken ◽  
...  
Keyword(s):  
Computed Tomography ◽  
Lung Cancer ◽  
Low Dose ◽  
Low Dose Computed Tomography

Plasticity and the Human Brain: Insights from Functional Imaging

1996 ◽  
Vol 2 (6) ◽  
pp. 353-362 ◽  
Author(s):  
Richard S.J. Frackowiak
Keyword(s):  
Human Brain ◽  
Functional Imaging ◽  
Large Scale ◽  
Imaging Techniques ◽  
Functional Reorganization ◽  
Neuronal Populations ◽  
Normal Behavior ◽  
Definition Of ◽  
The Brain

This article begins with a definition of cerebral plasticity in human brain that rests on the concept of a long-term alteration in patterns of task- or behavior-related activity in distributed brain systems. The theme is then developed to show how such a concept and the mechanisms it implies can be investigated and mapped using modern noninvasive functional imaging techniques. The human experimental literature is critically presented in relation to normal behavior, especially in relation to the acquisition of motor skills and learning. A discussion of the functional reorganization that follows brain injury and that is associated with spontaneous recovery from motor and perceptual deficits is then presented from the perspective of understanding the brain mechanisms at the level of large-scale neuronal populations.

scholarly journals Primary Prevention of CVD with Aspirin: Benefits vs Risks

2021 ◽  
Vol 70 (6 Supplement) ◽  
Author(s):  
Weisman
Keyword(s):  
Primary Prevention ◽  
Large Scale ◽  
Low Dose ◽  
Absolute Increase ◽  
Increased Risk ◽  
Low Dose Aspirin ◽  
Clinical Consequences ◽  
History Of ◽  
Ischemic Attack

Low-dose aspirin (acetylsalicylic acid [ASA]; 75 to 100 mg/d) is widely used in the prevention of cardiovascular (CV) events based on the results of large-scale studies supporting a benefit. However, questions remain regarding the benefit-risk relationship in certain settings since long-term use of ASA is not devoid of risk. Incontrovertible evidence supports the benefits of ASA treatment, which exceed the risks, in patients who have had a previous CV event (myocardial infarction, stroke, unstable angina, or transient ischemic attack). Nonetheless, the question remains for those patients who have not had a previous event (primary prevention), where the risk of CV events is lower and, consequently, the absolute benefit is also lower than in patients who have a history of a CV event or its equivalent (secondary prevention). Recent evidence from large-scale clinical trials shows that administration of low-dose ASA is associated with a reduced risk of CV events with a corresponding small absolute increase in the risk of major bleeding (eg, gastrointestinal bleeding and hemorrhagic stroke). Although the benefit and the risk of low-dose ASA in primary prevention are numerically similar, the clinical consequences of an increased risk of bleeding and a decreased risk of a CV event may not be equivalent. If these data are applied to patients with higher levels of CV outcome risk, more patients may potentially benefit from aspirin use in primary prevention.

scholarly journals X-ray in-line holography and holotomography at the NanoMAX beamline

2022 ◽  
Vol 29 (1) ◽  
Author(s):  
Sebastian Kalbfleisch ◽  
Yuhe Zhang ◽  
Maik Kahnt ◽  
Khachiwan Buakor ◽  
Max Langer ◽  
...  
Keyword(s):  
Electron Density ◽  
Low Dose ◽  
Focal Spot ◽  
Chemical Elements ◽  
Imaging Techniques ◽  
High Sensitivity ◽  
X Ray ◽  
X Ray Imaging ◽  
Dose Imaging ◽  
2D And 3D

Coherent X-ray imaging techniques, such as in-line holography, exploit the high brilliance provided by diffraction-limited storage rings to perform imaging sensitive to the electron density through contrast due to the phase shift, rather than conventional attenuation contrast. Thus, coherent X-ray imaging techniques enable high-sensitivity and low-dose imaging, especially for low-atomic-number (Z) chemical elements and materials with similar attenuation contrast. Here, the first implementation of in-line holography at the NanoMAX beamline is presented, which benefits from the exceptional focusing capabilities and the high brilliance provided by MAX IV, the first operational diffraction-limited storage ring up to approximately 300 eV. It is demonstrated that in-line holography at NanoMAX can provide 2D diffraction-limited images, where the achievable resolution is only limited by the 70 nm focal spot at 13 keV X-ray energy. Also, the 3D capabilities of this instrument are demonstrated by performing holotomography on a chalk sample at a mesoscale resolution of around 155 nm. It is foreseen that in-line holography will broaden the spectra of capabilities of MAX IV by providing fast 2D and 3D electron density images from mesoscale down to nanoscale resolution.

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