The molecular hydrogen ion H₂⁺ is the simplest molecule. This simplicity makes it a perfect study object for physicists, as its properties—for example, its energy levels—can be calculated precisely.

Laser Doppler flowmetry (LDF) has long been considered a gold standard for non-invasive assessment of skin microvascular function. Due to the laser Doppler (LD) microcirculatory signal’s complex ...

Patients with postural orthostatic tachycardia syndrome (POTS) experience an excessive increase in heart rate (HR) and low-frequency (∼0.1 Hz) blood pressure (BP) and HR oscillations upon head-up tilt ...

Persistent congestion with deteriorating renal function is an important cause of adverse outcomes in heart failure. We aimed to characterize new approaches to evaluate renal congestion using Doppler ...

Atrial fibrillation (AF) is the most common heart rhythm disturbance and is associated with substantial morbidity and mortality. The overall prevalence of AF varies from 2% to 5% of the general ...

Ionization of molecules by hard X-ray photons induces ultrafast rotation up to an effective rotational temperature of about 10,000 K due to the recoil caused by emission of a fast photoelectron. The ...

For our companion piece and final conclusions on the style after blind-tasting 324 of these beers, read today’s The State of IPA: Hazy, Juicy, Sludgy and Confused. How do you introduce the largest ...

Edited by John H. Seinfeld, California Institute of Technology, Pasadena, CA, and approved October 14, 2016 (received for review August 1, 2016) ...

Vortex light carries orbital angular momentum (OAM) characterized by exp(ilθ), where θ is the angular coordinate and l is the topological charge (TC) 1. OAM beams have been widely used in a variety of ...

A frequency shift experienced by an observer whenever a source of waves moves away from or towards the observer is a feature common to all waves — a phenomenon called the Doppler effect. Indeed, ...

If you've ever received a speeding ticket or enjoyed a night watching TGIF in the 1990s, then you can thank Albert Einstein. This week marks a century since the patent clerk-turned-physicist presented ...

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