Publications by authors named "Christopher J Pugh"

We consider a microscopy setting where quantum light is used for illumination. Spontaneous parametric down conversion (SPDC) is used as a source of a heralded single photon, which is quantum light prepared in a Fock state. We present analytical formulas for the spatial mode tracking along with the heralded and non-heralded mode widths.

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Intermittent claudication (IC) is associated with impairments in quality of life and walking ability. Heat therapy is an emerging cardiovascular therapy, which may improve walking in patients with IC. We undertook a systematic review to establish current evidence for heat therapy for patients with IC.

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Despite its widespread use in fiber optics, encoding quantum information in photonic time-bin states is usually considered impractical for free-space quantum communication as turbulence-induced spatial distortion impedes the analysis of time-bin states at the receiver. Here, we demonstrate quantum key distribution using time-bin photonic states distorted by turbulence and depolarization during free-space transmission. Utilizing a novel analyzer apparatus, we observe stable quantum bit error ratios of 5.

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Article Synopsis
  • This study investigates how different intensity levels of double-leg press exercise affect the mechanics of the common carotid artery (CCA) using advanced imaging techniques.
  • Researchers tested 15 healthy men during and after exercise at 30% and 60% of their maximum strength, measuring various strain metrics and arterial properties.
  • The findings revealed that while peak circumferential strain and systolic strain rate decreased during exercise, they increased significantly afterwards, indicating that CCA wall mechanics may offer insights into vascular responses beyond what current stiffness measures reveal.
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Correlated photon pairs produced by a spontaneous parametric down conversion (SPDC) process can be used for secure quantum communication over long distances including free space transmission over a link through turbulent atmosphere. We experimentally investigate the possibility to utilize the intrinsic strong correlation between the pump and output photon spatial modes to mitigate the negative targeting effects of atmospheric beam wander. Our approach is based on a demonstration observing the deflection of the beam on a spatially resolved array of single photon avalanche diodes (SPAD-array).

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Article Synopsis
  • Technological limitations constrain terrestrial quantum key distribution (QKD) to distances of just a few hundred kilometers.
  • A potential solution for wider quantum communication is utilizing low-Earth-orbit satellites.
  • This study demonstrates successful QKD from a stationary transmitter to a moving receiver, simulating satellite conditions, achieving a secure key generation rate of 40 bits/s while addressing various technical challenges.
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Non-alcoholic fatty liver disease (NAFLD) is associated with multi-organ (hepatic, skeletal muscle, adipose tissue) insulin resistance (IR). Exercise is an effective treatment for lowering liver fat but its effect on IR in NAFLD is unknown. We aimed to determine whether supervised exercise in NAFLD would reduce liver fat and improve hepatic and peripheral (skeletal muscle and adipose tissue) insulin sensitivity.

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Purpose: We performed two experiments to determine whether cutaneous microvascular adaptations in response to repeated core temperature (Tc) elevation are mediated by increases in skin blood flow (SkBF) and/or skin temperature.

Methods: Healthy subjects participated for 8 wk in thrice-weekly bouts of 30-min lower limb heating (40°C). In study 1, both forearms were "clamped" at basal skin temperature throughout each heating bout (n = 9).

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Nonalcoholic fatty liver disease (NAFLD) is an independent risk factor for cardiovascular disease (CVD). Endothelial dysfunction is an early manifestation of atherosclerosis and an important prognostic marker for future cardiovascular events. The aim of this study was twofold: to examine 1) the association between liver fat, visceral adipose tissue (VAT), and endothelial dysfunction in obese NAFLD patients and 2) the impact of supervised exercise training on this vascular defect.

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Introduction: Regular exercise induces recurrent increases in cerebrovascular perfusion. In peripheral arteries, such episodic increases in perfusion are responsible for improvement in arterial function and health. We examined the hypothesis that exercise during immersion augments cerebral blood flow velocity compared with intensity-matched land-based exercise.

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The objectives of our study were to examine 1) the proportion of responders and nonresponders to exercise training in terms of vascular function; 2) a priori factors related to exercise training-induced changes in conduit artery function, and 3) the contribution of traditional cardiovascular risk factors to exercise-induced changes in artery function. We pooled data from our laboratories involving 182 subjects who underwent supervised, large-muscle group, endurance-type exercise training interventions with pre-/posttraining measures of flow-mediated dilation (FMD%) to assess artery function. All studies adopted an identical FMD protocol (5-min ischemia, distal cuff inflation), contemporary echo-Doppler methodology, and observer-independent automated analysis.

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Non-alcoholic fatty liver disease (NAFLD), characterized by lipid deposition within the liver [intrahepatocellular lipid (IHCL)], is associated with insulin resistance and the metabolic syndrome (MS). It has been suggested that impaired skeletal muscle mitochondrial function may contribute to ectopic lipid deposition, and the associated MS, by altering post-prandial energy storage. To test this hypothesis, we performed a cross-sectional study of 17 patients with NAFLD [mean±S.

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The aim of this study was to examine the contribution of arterial shear to changes in flow-mediated dilation (FMD) during sympathetic nervous system (SNS) activation in healthy humans. Ten healthy men reported to our laboratory four times. Bilateral FMD, shear rate (SR), and catecholamines were examined before/after 10-min of -35-mmHg lower body negative pressure (LBNP10).

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Episodic increases in cerebrovascular perfusion and shear stress may have beneficial impacts on endothelial function that improve brain health. We hypothesized that water immersion to the level of the right atrium in humans would increase cerebral perfusion. We continuously measured, in 9 young (means ± SD, 24.

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Purpose: Shear stress is a known stimulus to vascular adaptation in humans. However, it is not known whether thermoregulatory reflex increases in blood flow and shear can induce conduit artery adaptation.

Methods: Ten healthy young volunteers therefore underwent 8 weeks of 3 × weekly bouts of 30 min lower limb heating (40 °C) during which the upper body was not directly heated.

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Introduction: Polycystic ovarian syndrome (PCOS) is associated with an adverse cardiovascular disease (CVD) profile. A surrogate marker for CVD risk is endothelial dysfunction. Limited studies exist examining the cardiovascular and metabolic effects of exercise in PCOS and specifically its impact on endothelial function.

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PCOS (polycystic ovary syndrome) is associated with IR (insulin resistance), increased visceral fat and NAFLD (non-alcoholic fatty liver disease) all of which may contribute to endothelial dysfunction, an early marker of CVD (cardiovascular disease) risk. Our objective was to examine the relationships between endothelial dysfunction in PCOS, the volume of AT (adipose tissue) compartments and the size of intracellular TAG (triacylglycerol) pools in liver and skeletal muscle. A total of 19 women with PCOS (means±S.

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Objectives: To assess whether exergaming can induce measurable changes in heart rate (HR), energy expenditure (EE), and flow-mediated dilation (FMD) arterial function in healthy children.

Study Design: Fifteen children (8 males, 10.1 ± 0.

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The leading causes of mortality in nonalcoholic fatty liver disease (NAFLD) relate to cardiovascular disease (CVD). The contribution of nitric oxide (NO) to endothelial function, a surrogate of CVD risk, is currently unknown in NAFLD. We hypothesize that NO-mediated cutaneous microvessel function would be impaired in NAFLD compared with controls and that exercise would enhance microvessel function compared with conventional care.

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Context: Nonalcoholic fatty liver disease may be evident in women with polycystic ovary syndrome (PCOS), both conditions being associated with obesity and insulin resistance. However, few studies have accounted for the high prevalence of obesity in PCOS.

Objective: The aim of this study was to determine whether PCOS is independently associated with hepatic steatosis, compared with healthy controls of similar age and body mass index (BMI), and whether steatosis is associated with hyperandrogenemia.

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Objective: Women with polycystic ovary syndrome (PCOS) demonstrate an increased prevalence of cardiovascular disease (CVD) risk factors. Previous researchers have compared flow-mediated dilation (FMD), an early marker of CVD, in women with and without PCOS. Evidence for a PCOS-mediated reduction in FMD remains equivocal, potentially because of study differences in cohort-matching and measurement approaches.

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