Rotational atherectomy

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Cardiovascular Outcomes Following Rotational Atherectomy: A UK Multicentre Experience

Cardiovascular Outcomes Following Rotational Atherectomy: A UK Multicentre Experience

Rotational atherectomy (RA) is an effective way of mechanically modifying and debulking calcified coronary artery lesions; according to ESC guidelines for revascularization it has a Class 1 recommendation for preparation of heavily calcified or severely fibrotic lesions that cannot be crossed by a balloon or adequately dilated before planned stenting (3). Given the positive relationship between residual plaque burden behind the stent and the amount of neointimal proliferation post-stenting, it had been hoped that the use of RA may reduce long term restenosis (4, 5). However, the randomised ROTAXUS study showed no benefit in angiographic restenosis using RA and paclitaxel eluting stents (PES) compared to a conservative strategy without RA during a 9 month follow up period (1).
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Original Article Effect of coronary rotational atherectomy before stent implantation on serum inflammatory and plaque stabilization factors in patients with coronary artery disease

Original Article Effect of coronary rotational atherectomy before stent implantation on serum inflammatory and plaque stabilization factors in patients with coronary artery disease

Therefore, timely and effective measures to remove calcified plaques in coronary arteries may improve PCI results [5]. Coronary rotation- al atherectomy can ablate these plaques, en- larging the arterial lumen and softening remain- ing plaque tissue, which facilitates smooth operation during cardiovascular coronary sur- gery. On the other hand, research has shown that the severity of the coronary plaque and the level of inflammatory factors and plaque stabili- zation factors are positively correlated, with plaque promoting inflammation. Inflammation appears to peak and then begin to decline 72 hours after PCI, with plaque rotational ablation reducing compression of the stent to the pl- aque, thus reducing inflammation. Therefore, plaque reduction and vascular re-conduction could decrease serum levels of inflammatory markers [6, 7]. In this study, we aim to provide a theoretical basis for the clinical application of coronary rotational atherectomy in cardiovas- cular interventional surgery based on its clini- cal effects on serum inflammation factors and plaque stabilization indicators.
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Temporal changes in radial access use, associates and outcomes in patients undergoing PCI using rotational atherectomy between 2007 and 2014: results from the British Cardiovascular Intervention Society national database.

Temporal changes in radial access use, associates and outcomes in patients undergoing PCI using rotational atherectomy between 2007 and 2014: results from the British Cardiovascular Intervention Society national database.

Aims: Access site choice for cases requiring rotational atherectomy (PCI-ROTA) is poorly defined. Using the British Cardiovascular Intervention Society PCI database, temporal changes and contemporary associates/outcomes of access site choice for PCI-ROTA were studied. Methods and Results: Data were analysed from 11,444 PCI-ROTA procedures performed in England and Wales between 2007 and 2014. Multivariate logistic regression was used to identify predictors of access site choice and its association with outcomes. Results: For PCI-ROTA, radial access increased from 19.6% in 2007 to 58.6% in 2014. Adoption of radial access was slower in females, those with prior CABG, and in patients with chronic occlusive (CTO) or left main disease. In 2013/14, the strongest predictors of femoral artery use were age (OR 1.02, [1.005-1.036], p=0.008), CTO intervention (OR 1.95, [1.209-3.314], p=0.006), and history of previous CABG (OR 1.68, [1.124-2.515], p=0.010). Radial access was associated with reductions in overall length of stay, and increased rates of same-day discharge. Procedural success rates were similar although femoral access use was associated with increased access site complications (2.4 vs. 0.1%, p<0.001). After adjustment for baseline differences, arterial complications (OR 15.6, p<0.001), transfusion (OR 12.5, p=0.023) and major bleeding OR 6.0, p<0.001) remained more common with FA use. Adjusted mortality and MACE rates were similar in both groups. Conclusions: In contemporary practice, radial access for PCI-ROTA results in similar procedural success when compared to femoral access but is associated with shorter length of stay, and lower rates of vascular complication, major bleeding and transfusion.
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Experimental and numerical investigation of orbital atherectomy: absence of cavitation

Experimental and numerical investigation of orbital atherectomy: absence of cavitation

Attention will now be turned to a discussion of what appears to be the only report of the creation of cavitation bubbles by rotational atherectomy [22]. There are sev- eral reasons why the observations reported in this refer- ence may be viewed with some uncertainty. First, the time of bubble collapse reported there is on the order of minutes. Since the involved bubbles had radii on the order of 100 µm, the collapse time should have been in the range of 10 µs according to the aforementioned findings of [21]. Figure 1 of [22] shows that the radial distribution of the bubbles is the same both adjacent to the rotating crown and adjacent to the shaft to which the crown is affixed. However, the rotational velocities at the surface of the crown and at the surface of the bare shaft appear to differ by an order of magnitude, thereby giving rise to very different pressures adjacent to the bare shaft and the crown. In this light, it is difficult to justify comparable distributions of bubbles adjacent to the crown and the bare shaft. Photographs of the bubble field presented in Figures 6 and 7 of [22] show the pres- ence of bubbles in regions distal to the crown that do not contain a rotating device. The mechanism for the crea- tion of the latter-named bubbles is, therefore, unclear.
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Coronary Flow Reserve Assessment of Orbital Atherectomy: An Observational Pilot Study

Coronary Flow Reserve Assessment of Orbital Atherectomy: An Observational Pilot Study

Lastly, recent research comparing OA versus RA utilizing another measure of coronary microvascular function called index of myocardial resistance (IMR) indicated significantly lower IMR in the OA group compared to the RA group, suggesting preserved microvascular function post OA [18]. The CFR observa- tional pilot study reported herein and the recent IMR results has generated the hypothesis that OA results in better microvasculature function post treatment than RA. To test this hypothesis, the prospective ORACLE (Comparison of Orbital Versus Rotational Atherectomy Effects on Coronary Microcirculation in PCI) randomized control trial (n = 40) was designed and is currently enrolling subjects. The ORACLE trial will use IMR, post-procedural cardiac enzymes, and cardiac MRI to assess microvascular abnormalities after atherectomy (ClinicalTrials.gov Identifier: NCT03021577).
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Rethink Atherectomy: Expert Insights Into Clinical Application and Use of the JETSTREAM System

Rethink Atherectomy: Expert Insights Into Clinical Application and Use of the JETSTREAM System

across the aortoiliac bifurcation over a .035" guide wire with fluoroscopic guidance and advanced to the left external iliac artery. A 5,000 unit bolus of intravenous heparin was given and the ACT was maintained >250 seconds during the pro- cedure. The lesion was crossed with a .014" JETSTREAM JETWIRE and advanced into the superficial femoral artery. We then performed rotational atherectomy with dynamic as- piration using the JETSTREAM device. Several slow passes were made with the cutter blades down (2.1 mm) and up (3.0 mm). The device was slowly advanced with each pass in a back and forth motion, maintaining roughly 70,000 RPMs. Ather- ectomy was followed by dilatation with a 5.0 mm balloon for 3 minutes at 6 atm. Repeat angiography demonstrated a mild (<30%) eccentric residual stenosis. Post-atherectomy and an- gioplasty IVUS demonstrated significant improvement in the lesion with a CSA of 12.5 mm 2 and significant reduction in
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Rotational modulation in TESS B stars

Rotational modulation in TESS B stars

v sin i and will thus appear to confirm rotational modulation. A single low frequencies or a low frequency and its har- monic could possibly arise from SPB pulsation simply by coincidence. There is no known mechanism which preferen- tially selects just a single mode or a mode and its harmonic. Unless evidence for such a selection mechanism is found, it is difficult to accept SPB as a possible explanation for more than a few stars. In any case, pulsation can only occur if the star is within the instability strip. While the SPB instability strip may be extended to cooler stars by the effect of rota- tion, this explanation will ultimately fail for sufficiently cool stars. There are plenty of hot A stars which show a single low frequency or low frequency and harmonic well outside the SPB instability strip, no matter how much it can reason- ably be extended. These cannot be due to SPB pulsation. It is thus reasonable to assume that a single peak or a peak and its harmonic, for which the evidence indicates rotational modulation in A stars, is also a result of rotational modula- tion in the B stars.
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Influence of rotational inertia on turning performance of theropod dinosaurs: clues from humans with increased rotational inertia

Influence of rotational inertia on turning performance of theropod dinosaurs: clues from humans with increased rotational inertia

For an animal to turn sharply, it must change the direction of travel of its center of mass to a new heading and it must rotate its body to face the new heading. The ability of individuals to do this rapidly often influences the outcome of predator/prey and intraspecific competitions (Boswell, 1981; Willock and Pearson, 1992). Although there are a number of important studies of the mechanics of turning (Howland, 1974; Andrews et al., 1977; Thollesson and Norberg, 1991; Van Den Berg and Rayner, 1995; Jindrich and Full, 1999), relatively little is known about how animals produce sharp turns; nor do we fully understand the anatomical and physiological characters that influence turning performance. One character that can be expected to influence turning performance is the rotational inertia (i.e. moment of inertia) of a body. The rotational inertia (I) of a body is the sum of differential elements of mass (m) multiplied by the square of their perpendicular distances (r) from the axis of rotation: (I=Σm i r i 2 ). The perpendicular distance of a mass element
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Rotational  Cryptanalysis  of  ARX  Revisited

Rotational Cryptanalysis of ARX Revisited

Abstract. Rotational cryptanalysis is a probabilistic attack applicable to word oriented designs that use (almost) rotation-invariant constants. It is believed that the success probability of rotational cryptanalysis against ci- phers and functions based on modular additions, rotations and XORs, can be computed only by counting the number of additions. We show that this simple formula is incorrect due to the invalid Markov cipher assumption used for computing the probability. More precisely, we show that chained modular additions used in ARX ciphers do not form a Markov chain with regards to rotational analysis, thus the rotational probability cannot be computed as a simple product of rotational probabilities of individual modular additions. We provide a precise value of the probability of such chains and give a new algorithm for computing the rotational probability of ARX ciphers. We use the algorithm to correct the rotational attacks on BLAKE2 and to provide valid rotational attacks against the simplified version of Skein.
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Red giants rotational splittings

Red giants rotational splittings

the observed red giants, some spectra do not show any regular or close to regular structures. We expect these spectra to correspond to rapid rotators. In this case, modes of different azimuthal orders are of very different nature. The concept of rotational splitting of modes with the same radial distribution and different m is no longer relevant, and one should consider separately sub-spectra associated to each values of m. Provided that the rotation is high enough to give rise to clearly different distributions with respect to m, a new seismic diagnostic can be found by exploiting the differences of period spacings associated to each m. That corresponds to the very rapid rotation case i.e. for c /(2)/P /P 2 20. An intermediate case remains, where the rotational splitting is no longer a relevant seismic diagnostic, but where the rotation is too slow to allow to distinguish three different period spacings associated to the m families of modes (for X c / (2p) × DP / P 2 between 5 and 20). Establishing a proper diagnostic in
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Digital rotational radiography in neuroradiology

Digital rotational radiography in neuroradiology

3.-A, A clear differentiation between loop and dissection is not possible with conventional digital angiograms of left carotid artery, even with multiple views... SCHUMACHER ET AL..[r]

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Rotational Dynamics: An Exciting Challenge

Rotational Dynamics: An Exciting Challenge

In this book the author describes the deductive process followed that led to the Theory of Dynamic Interactions (TDI) . It studies inertial forces and incor- porates inertial reactions, also the concept of the gyroscopic torque , to the structure of a new, rotational dynamics of accelerated systems. The proposed theory generalises these dynamic concepts which had become de-structured in classical mechanics, and enables us to confirm and understand the physical and mathematical correlation that holds between orbiting and intrinsic rotation and, therefore, the reason why we have day and night on Earth (see Figure 5).
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Rotational  isomerism in Dioeloroacetyl Ealides

Rotational isomerism in Dioeloroacetyl Ealides

Infrared, and Raman speotra have been measured for CEOlgOOF, CEGI2COCI and CEOlgOOBr and it is concluded that two molecular forms eziat in the vapour and liquid phases, of which the more[r]

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Population of rotational bands in superheavy nuclei

Population of rotational bands in superheavy nuclei

Experimental study of rotational bands of superheavies is especially hopeful, as the limits of sta- bility of these nuclei in spin and excitation energy are governed by the fission barrier, which is mostly defined by shell component. The investigation of high-spin spectra also provides information about angular momentum dependence of the shell effects. Unfortunately, there are still a little experimental data for the heaviest evaporation residues, as their production cross sections are too small for the spec- troscopical analysis. However, using the in-beam studies, the structure of high-spin excited states up to ∼ 20 ~ has been recently identified for the nuclei 254 No, 252 No, and 250 Fm, produced with the cross sections 0.2–3 µb [7–10].
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Evolutionary Optimization of Rotational Population Transfer

Evolutionary Optimization of Rotational Population Transfer

transfer to NO(J = 9/2) is only 25% (at an intensity of 4 × 10 13 W/cm 2 ). When increasing the intensity of an FTL pulse, the population distribution is spread over a large range of rotational states resulting in a drop in transfer efficiency to a particular state. However, when increasing the intensity, the CMA-ES procedure consistently leads to a better population transfer to a target state. The highest population that we observed was 98.9% for optimizations targeting NO(J = 5/2) and 97.7% for optimizations targeting NO(J = 9/2). Figure 4 suggests that without the constraint imposed by the finite pulse energy, a 100% yield may be possible [14], a remarkable result in an infinite ladder system. At an intensity of 4 × 10 13 W/cm 2 , which is our best estimate of the intensity reached in the experiment when the laser pulse is compressed to a FTL laser pulse, the highest yield in our optimal control simulations targeting NO(J = 5/2) and NO(J = 9/2) is 70.4% and 42%, respectively. Considering the uncertainty in the intensity as well as the intensity fluctuations, these values are quite close to those obtained experimentally. We note that the pulse shapes found experimentally and theoretically (see Fig. 5) are very similar. In the case of J = 5/2, the pulse shape is dominated by three peaks separated by 2.6 ps, with a similar substructure around the first pulse at −2.6 ps. This solution is, moreover, quite robust since the algorithm always found this pulse sequence over the seven runs performed. Upon increasing the intensity in our calculations, this robustness vanishes. The solutions found by the algorithm become rather complicated and are different for each run. Each run still achieves a very high degree of population transfer. Our experimental results in which a unique solution is found show that constraints not only impact the efficiency of the optimization process, but also impose limitations on the controllability of the system,
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Rotational oscillation of a cylinder in 
		air flow

Rotational oscillation of a cylinder in air flow

The paper describes the experimental study of shielding effects of the disk placed coaxially upstream of a cylinder. It not only reduces the drag of the cylinder. The disk changes the dynamic characteristics of the cylinder. Without a disk, an elastically fixed cylinder in the airflow performs rotational oscillations with constant amplitude. A disk of small diameter, located near the cylinder, reduces the amplitude of rotational oscillation. Increasing the distance between the disk and the cylinder causes the damped rotational oscillations. The influence of the aerodynamic force on the damping of the oscillations depends on the disk diameter and the gap between disk and cylinder. A mathematical model is proposed for describing the rotational steady and damped oscillation of a cylinder with a disk.
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Rotational  cryptanalysis  of  round-reduced  Keccak

Rotational cryptanalysis of round-reduced Keccak

First, we describe the preimage attack on 3-round Keccak -512 which is based on the rotational distinguisher given in the previous section. Then we show how to extend the attack to 4 rounds. To have the attack working on Keccak hash function, we have to consider padding and Keccak parameters. Let us consider Keccak -512 which has r = 576, c = 1024 and a hash length set to 512 bits. For the preimage attack we propose the following structure of the message. A message length is 574 bits, where first 8 lanes (512 bits) are unknown (to be determined by the attacker). Last 62 bits of the message are set to 1. The message is padded with two 1’s giving a block of 576 bits. This way we fulfil a condition that all lanes (except first 8 lanes) have all 0’s or 1’s. We would use similar constraints on a message when attacking Keccak with different parameters (including all Keccak variants proposed as SHA-3 candidates).
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Rotational Inertia and Angular Momentum Hewitt.pptx

Rotational Inertia and Angular Momentum Hewitt.pptx

The three principal axes of rotation in the human body are the longitudinal axis, the transverse axis, and the medial axis... The human body can rotate freely about three principal ax[r]

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Rotational Effects Of Legumes On Maize Yield

Rotational Effects Of Legumes On Maize Yield

The bulk of maize in Ghana is grown in the forest-savanna transition zone of the country. Two crops of maize can be grown per year in this zone. However low soil fertility is a major factor limiting crop yields. Crop rotation with legumes improves soil properties [4], [2], [9], [17] and might therefore reduce mineral fertilizer requirements of succeeding non- leguminous crops. Crop rotation also influences N use efficiency and prompt changes in various N sources, affecting availability to the plant [11]. Canavalia ensiformis, Mucuna pruriens, Glycine max, and Vigna unguiculata have been reported to potentially contribute considerable amounts of N to succeeding crops [14], [13], [12]. However, most legumes cannot provide sufficient N to meet the potential demand of maize following them in a rotational system. Codjia (1996), studying the response of maize to Mucuna pruriens and Mucuna cochinchinensis with various rates of chemical fertilizer, observed a 98% increase in maize grain yields without chemical fertilizer and a 179% increase with 51 kg N, 46 kg P and 28 kg K/ha. In experiments conducted by [3], maize grown after grain legumes (cowpea and soybean) and legume cover crops yielded 15.1-24.6% and 30.3-42.5% higher than maize- maize cropping system respectively. Asibuo (1999) also reported higher maize grain yield when he applied 45 kg N, 18 kg P and 18 kg K/ha to maize planted after Mucuna pruriens, groundnut and cowpea than when no fertilizer was applied. Several studies have been done on legume/maize rotation systems. However, most of these studies did not include economic analysis of the systems. The objective of the study was therefore to determine maize grain yield responses to fertilizer N as affected by preceding legume crops and economic implication of the study.
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