The preponderance of matter over antimatter in the early Universe, the dynamics of the supernova bursts that produced the heavy elements necessary for life and whether protons eventually decay -these mysteries at the forefront of particle physics and astrophysics are key to understanding the early evolution of our Universe, its current state and its eventual fate. The Long-Baseline Neutrino Experiment (LBNE) represents an extensively developed plan for a world-class experiment dedicated to addressing these questions.Experiments carried out over the past half century have revealed that neutrinos are found in three states, or flavors, and can transform from one flavor into another. These results indicate that each neutrino flavor state is a mixture of three different nonzero mass states, and to date offer the most compelling evidence for physics beyond the Standard Model. In a single experiment, LBNE will enable a broad exploration of the three-flavor model of neutrino physics with unprecedented detail. Chief among its potential discoveries is that of matter-antimatter asymmetries (through the mechanism of charge-parity violation) in neutrino flavor mixing -a step toward unraveling the mystery of matter generation in the early Universe. Independently, determination of the unknown neutrino mass ordering and precise measurement of neutrino mixing parameters by LBNE may reveal new fundamental symmetries of Nature.Grand Unified Theories, which attempt to describe the unification of the known forces, predict rates for proton decay that cover a range directly accessible with the next generation of large underground detectors such as LBNE's. The experiment's sensitivity to key proton decay channels will offer unique opportunities for the ground-breaking discovery of this phenomenon.Neutrinos emitted in the first few seconds of a core-collapse supernova carry with them the potential for great insight into the evolution of the Universe. LBNE's capability to collect and analyze this high-statistics neutrino signal from a supernova within our galaxy would provide a rare opportunity to peer inside a newly-formed neutron star and potentially witness the birth of a black hole.To achieve its goals, LBNE is conceived around three central components: (1) a new, highintensity neutrino source generated from a megawatt-class proton accelerator at Fermi National Accelerator Laboratory, (2) a fine-grained near neutrino detector installed just downstream of the source, and (3) a massive liquid argon time-projection chamber deployed as a far detector deep underground at the Sanford Underground Research Facility. This facility, located at the site of the former Homestake Mine in Lead, South Dakota, is ∼1,300 km from the neutrino source at Fermilab -a distance (baseline) that delivers optimal sensitivity to neutrino charge-parity symmetry violation and mass ordering effects. This ambitious yet cost-effective design incorporates scalability and flexibility and can accommodate a variety of upgrades and contributions.With its exceptional combi...
We have observed many focal dilatations or very small aneurysms in terminal arterioles and capillaries of 4 of 5 patients and 6 dogs who had recently undergone cardiopulmonary bypass. A smaller number of sausagelike dilatations distended medium-sized arterioles. Two other patients had a small number of the same microvascular changes following proximal aortography. Thirty-four patients and 6 dogs not undergoing cardiopulmonary bypass had none. (A 35th patient who had not undergone cardiopulmonary bypass or aortography showed a small number of dilatations; mediastinal air was a suggested source.) Some of the dilatations exhibited various forms of birefringence. Because most of the dilatations appear empty, we speculate that they are the sites of gas bubbles or fat emboli that have been removed by the solvents used in processing. These microvascular events, occurring only in conjunction with major arterial interventions, may be the anatomical correlate of the neurological deficits or moderate to severe intellectual dysfunction seen in at least 24% of patients after cardiac surgical procedures assisted by cardiopulmonary bypass.
SPM-5185 reduces myocardial necrosis and neutrophil accumulation in an acute model of canine myocardial ischemia and reperfusion. This reduction in myocardial cell injury may be partially related to the inhibitory actions of this novel NO donor on neutrophil adherence to the coronary endothelium.
Three measures of left ventricular (LV) performance derived from pressure (P)-volume (V) loops have been proposed: the end-systolic P-V (PES-VES) relation, the stroke workend-diastolic V (SW-VED) relation, and maximum dP/dt-VED (dP/dtmax-VED) relation. We evaluated the variability of repeated determinations, and inotropic and load sensitivity of these relations in conscious dogs. LVV was determined from three orthogonal LV diameters measured by sonomicrometry. Three to six sets of variably loaded P-V loops were generated by transient caval occlusions before and again after increasing inotropic state by infusing dobutamine (6±1 ug/kg/min, mean+SD) and after increasing PEs by 49±17 mm Hg with phenylephrine following autonomic blockade. The slope (Msw) of the SW-VED relation was the least variable at constant inotropic state (coefficient of variation, 4±N3%) compared with the slope (EES) of the PES-VEs relation (8+±3%) or the slope (dE/dtmax) of the dP/dtmax-VED relation (11±6%, p
BackgroundAnalysis of lower limb exercises is traditionally completed with four distinct methods (i) 3D motion capture; (ii) depth-camera based systems (iii) visual analysis from a qualified exercise professional; (iv) self-assessment. Each method is associated with a number of limitations. ObjectiveThe aim of this systematic review is to synthesize and evaluate studies which have investigated the capacity for inertial measurement unit (IMU) technologies to assess movement quality in lower limb exercises. Data SourcesA systematic review of PubMed, ScienceDirect and Scopus was conducted. Study Eligibility CriteriaArticles written in English and published in the last 10 years which contained an IMU system for the analysis of repetition-based targeted lower limb exercises were included. Study Appraisal and Synthesis MethodsThe quality of included studies was measured using an adapted version of the STROBE assessment criteria for cross-sectional studies. The studies were categorised in to three groupings: exercise detection, movement classification or measurement validation. Each study was then qualitatively summarised. ResultsFrom the 2452 articles that were identified with the search strategies, 47 papers are included in this review. ConclusionsWearable inertial sensor systems for analysing lower limb exercises are a rapidly growing technology. Research over the past ten years has predominantly focused on validating measurements that the systems produce and classifying users' exercise quality. There have been very few user evaluation studies and no clinical trials in this field to date. Key PointsInertial measurement unit (IMU) systems have been extensively validated to successfully measure joint angle and temporal features during lower limb exercises.It is less understood if IMU systems can validly compute kinetic measures pertaining to lower limb exercises.IMU systems, which incorporate machine learning in to their data analysis pathways, have also been found to be effective in automated exercise detection and in classifying movement quality across a range of lower limb exercises.3
A mathematical model describing the dynamic interaction between the left and the right ventricle over the complete cardiac cycle is presented. The pericardium-bound left and right ventricles are represented as two coupled chambers consisting of the left and right free walls and the interventricular septum. Time-varying pressure-volume relationships characterize the component compliances, and the interaction of these components produces the globally observed ventricular pump properties (total chamber pressure and volume). The model 1) permits the simulation of passive (diastolic) and active (systolic) ventricular interaction, 2) provides temporal profiles of hemodynamic variables (e.g., ventricular pressures, volumes, and flow) that agree well with reported observations, and 3) can be used to examine the effect of the pericardium on ventricular interaction and ventricular mechanics. It can be reduced to equivalency with models previously reported by invoking simplifying assumptions. Furthermore, model-generated "dynamic interaction gains" are employed to quantify the mode and degree of ventricular interaction. The model also yields qualitative predictions of septal and free wall displacements similar to those detected experimentally via M-mode echocardiography. Such analogies may be extended easily to the study of pathophysiological states via appropriate modifications to 1) the pressure-volume characteristics of the component walls (and/or pericardium) and/or 2) the specific time course of activation of the ventricular free wall or the septum. A limited number of examples are included to demonstrate the utility of the model, which may be used as an adjunct to new experimental investigations into ventricular interaction.
We tested the hypothesis that intracoronary administration of L-arginine (L-Arg), the physiological nitric oxide (NO) precursor, during reperfusion would attenuate postischemic damage by L-Arg NO-pathway mechanisms. Open-chest, anesthetized dogs underwent 60 min of left anterior descending coronary arterial (LAD) occlusion followed by 270 min of reperfusion. Dogs received intracoronary 10 mM L-Arg (n = 9 dogs), intracoronary 10 mM D-arginine (D-Arg, n = 7), or saline vehicle (Veh, n = 10) in the LAD during the first 120 min of reperfusion using an extracorporeal system. After 270 min of reperfusion, segmental systolic and diastolic function were comparably impaired in all three groups. Infarct size (triphenyltetrazolium chloride) expressed as a percentage of the area at risk (An/Ar) was significantly (P < 0.05) reduced in the L-Arg group (17.7 +/- 3.2%) compared with the Veh group (34.8 +/- 2.4%); D-Arg reversed this cardioprotection (48.8 +/- 5.2%, P < 0.05 vs. L-Arg, Veh). Cardiac myeloperoxidase activity, an index of neutrophil accumulation (U/100 mg tissue), was significantly (P < 0.05) lower in the necrotic tissue of the L-Arg group (0.88 +/- 0.26) than in the Veh group (2.46 +/- 0.38). Furthermore, responses to endothelium-dependent vasodilators acetylcholine and A23187 in isolated ischemic-reperfused LAD rings were significantly (P < 0.05) greater in the L-Arg group than in the other two groups. We conclude that intracoronary infusion of L-Arg during the early phase of reperfusion reduced neutrophil accumulation and infarct size and the infusion preserved endothelial function, possibly by increasing NO release or production by the endothelium.
We conclude that 1) endogenous adenosine building up during ischemia is cardioprotective, and 2) pretreatment with adenosine confers cardioprotection independent of hemodynamic effects. Whether pretreatment effects of adenosine subsequently modulate the effects of endogenous adenosine (through alterations in receptor population or sensitivity) or endogenous and exogenous adenosine represent additive compartments is unclear.
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