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The catalytic mechanism is further revealed by in situ Raman analysis and density functional theory calculations.Magnetic resonance imaging generates unwanted acoustic noise. This review describes the work characterizing the acoustic noise, and the various solutions to control and attenuate the acoustic noise. There are also discussions about the permissible limits, and guidance regarding acoustic noise exposure for staff, patients, and volunteers. LEVEL OF EVIDENCE 5 TECHNICAL EFFICACY STAGE 1.Deep-ultraviolet nonlinear optical (DUV NLO) materials are attracting increasing attention because of their structural diversity and complexity. Using the two-dimensional (2D) crystal structure prediction method combined with the first-principles calculations, here we propose layered 18-membered-ring (18MR) boron oxide B2 O3 polymorphs as high-performance NLO materials. 18MR-B2 O3 with the AA and AB stackings are potential DUV NLO materials. The superior performing 18MR-B2 O3 AB has an unprecedentedly high second harmonic generation coefficient of 1.63 pm V-1 , the largest among the DUV NLO materials, three times larger than that of the advanced DUV NLO material KBe2 BO3 F2 and comparable to that of β-BaB2 O4 . Its unusually large birefringence of 0.196 at 400 nm guarantees the phase-matching wavelength λPM to reach this material’s extreme absorption edge of ≈154 nm.Electroanatomic mapping systems have become an essential tool to guide the identification and ablation of arrhythmic substrate. Recently, a novel guiding system for electrophysiology procedures was introduced that uses dielectric sensing to perform high resolution anatomical imaging. Dielectric imaging systems use electrical fields to differentiate anatomic structures based on their conductivity and permittivity. This technique enables non-fluoroscopic, noncontact mapping of anatomic structures, assessment of pulmonary vein occlusion state during cryoballoon ablation, and has the potential to assess for additional tissue characterization including tissue thickness and tissue type. This article elaborates on the functioning and potential of dielectric imaging systems and provides two cases to illustrate the clinical impact for electrophysiology procedures.Due to the increased number of patients suffering from asthma, the mechanism of this disease has been subject to much attention from the public and finding a cure for this disease is urgent. A changed abundance of the microbiome has been proven to play an important role in the genesis and development of asthma. In this study, the abundance and the function of the microbiome were studied. It was found that there were significant changes in the components and the function of the microbiome when asthma changed from mild to severe. This study could help us to better understand the relationship between asthma and the respiratory microbiome.
Sub-Saharan Africa (SSA) has long been characterised as a region with weak alcohol policies, high proportions of abstainers and heavy episodic drinkers (among drinkers), and as a target for market expansion by global alcohol producers. find more However, inter-regional analyses of these issues are seldom conducted.
Focusing mainly on the period 2000-2016, we compare alcohol consumption and harms, alcohol policy developments and alcohol industry activities over time and across the four sub-regions of SSA.
Per-capita consumption of alcohol and alcohol-related disease burden have increased in Central Africa but stabilised or reduced in other regions, although they are still high. Most countries have implemented tax policies, but they have seldom adopted other World Health Organization ‘best buys’ for cost-effective alcohol control policies. Countries range from having minimal alcohol controls to having total bans (e.g. some Muslim-majority countries); and some, such as Botswana, have attempted stringent tax policies to address alcohol harm. Alcohol producers have continued their aggressive marketing and policy interference activities, some of which have been highlighted and, in a few instances, resisted by civil society and public health advocates, particularly in southern Africa.
Increased government support and commitment are needed to be able to adopt and implement effective alcohol policies and respond to pressures from alcohol companies to which SSA remains a target market.
SSA needs effective alcohol control measures in order to reverse the trajectory of worsening alcohol harms observed in some countries and reinforce improvements in alcohol harms observed in others.
SSA needs effective alcohol control measures in order to reverse the trajectory of worsening alcohol harms observed in some countries and reinforce improvements in alcohol harms observed in others.
The dual crises of climate change and chronic, or non-communicable, disease (NCD) have emerged worldwide as the global economy has industrialized over the past two centuries.
In this synthesis I examine humans’ dependence on external (non-metabolic) energy expenditure (e.g., fire, fossil fuels) as a common, root cause in these modern crises.
Using fossil, archeological, and historical evidence I show that the human lineage has been dependent on external energy sources since the control of fire in the Paleolithic. This reliance has grown with the development of agriculture, the use of wind- and water-power, and the most recently with industrialization and the transition to fossil fuels. To place industrialization in context I develop a Rule of 50, whereby individuals in industrialized economies consume roughly 50-times more external energy and manufacture roughly 50-times more material than do hunter-gatherers.
Industrialization and mechanization, powered by fossil fuels, have promoted centralization aossil fuels is also critical to maintaining our species’ external energy portfolio.This pictorial review focuses on the ultrasound (US) appearance of the normal and pathological radial nerve (RN) and its branches and provides tips with which to locate them and avoid misinterpretation of normal findings. A wide range of our pathological cases are reviewed and presented to help in familiarizing the reader with common and uncommon clinical scenarios that affect the RN and its main branches.