Publications by authors named "Juan Arrazola"

The main objective was to evaluate structural and functional connectivity correlates of fatigue in post-COVID syndrome, and to investigate the relationships with an objective measure of mental fatigue and with subjective cognitive complaints. One-hundred and twenty-nine patients were recruited after 14.79 ± 7.

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Chronic subdural hematoma (CSDH) is a prevalent medical condition with potentially severe consequences if left untreated. While surgical removal has traditionally been the standard approach for treatment, middle meningeal artery (MMA) embolization has emerged as a promising minimally invasive alternative to reduce recurrences. This comprehensive review provides the general radiology community with an overview of MMA embolization as a therapeutic option for managing CSDH.

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Density functional theory (DFT) stands as a cornerstone method in computational quantum chemistry and materials science due to its remarkable versatility and scalability. Yet, it suffers from limitations in accuracy, particularly when dealing with strongly correlated systems. To address these shortcomings, recent work has begun to explore how machine learning can expand the capabilities of DFT: an endeavor with many open questions and technical challenges.

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Objectives: Magnetic resonance-guided focused ultrasound (MRgFUS) thalamotomy is a novel, minimally invasive ablative treatment for essential tremor (ET). The use of a four-tract probabilistic tractography technique, targeting the intersection between the dentato-rubro-thalamic tracts (both decussating and non-decussating), while evaluating the corticospinal tract and the medial lemniscus, may obtain immediate clinical results with reduced adverse events. Our aim is to present our experience with the four-tract technique for patients undergoing ET treatment with MRgFUS.

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Background: Cognitive deficits are among the main disabling symptoms in COVID-19 patients and post-COVID syndrome (PCS). Within brain regions, the hippocampus, a key region for cognition, has shown vulnerability to SARS-CoV-2 infection. Therefore, in vivo detailed evaluation of hippocampal changes in PCS patients, validated on post-mortem samples of COVID-19 patients at the acute phase, would shed light into the relationship between COVID-19 and cognition.

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Circuit design for quantum machine learning remains a formidable challenge. Inspired by the applications of tensor networks across different fields and their novel presence in the classical machine learning context, one proposed method to design variational circuits is to base the circuit architecture on tensor networks. Here, we comprehensively describe tensor-network quantum circuits and how to implement them in simulations.

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Objective: To demonstrate, by a cost-effectiveness analysis, the efficiency of mechanical thrombectomy (MT) versus medical management (MM) in patients with a low Alberta Stroke Program Early CT Score (ASPECTS) from the RESCUE Study.

Methods: A cost-effectiveness model was designed to project both direct medical costs and quality-adjusted life-years (QALYs) of MT versus MM in eight European countries (Spain, UK, France, Italy, Belgium, Germany, Sweden, and the Netherlands). Our model was created based on previously published health-economic data in those countries.

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Brain changes have been reported in the first weeks after SARS-CoV-2 infection. However, limited literature exists about brain alterations in post-COVID syndrome, a condition increasingly associated with cognitive impairment. The present study aimed to evaluate brain functional and structural alterations in patients with post-COVID syndrome, and assess whether these brain alterations were related to cognitive dysfunction.

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Background: Olfactory dysfunction is common during SARS-CoV-2 infection. The pathophysiology of the persistence of this symptom and the potential relationship with central nervous system involvement is unknown.

Aim Of The Study: To evaluate the neural correlates of persistent olfactory dysfunction in a series of patients with post-COVID syndrome.

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Background: The optimal endovascular treatment (EVT) technique for middle cerebral artery (MCA) M2 segment occlusions remains unknown. We aim to analyze whether reperfusion rate, procedure times, procedure-related complications, and clinical outcome differed between patients with isolated M2 occlusions who underwent stent-retriever (SR) alone versus combined SR and contact aspiration (CA) as a front-line EVT.

Methods: Patients who underwent EVT for isolated MCA-M2 occlusion were recruited from the prospectively ongoing ROSSETTI registry.

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Psoriasis is a common skin disease. Up to 30% of patients with psoriasis develop psoriatic arthritis (PsA) resulting, by far, the most prevalent coexisting condition. Heterogeneity of clinical and radiological presentation is a major challenge to diagnosis of PsA.

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Background: Anatomic variations in the hepatic venous system are the least understood aspect of hepatic anatomy. The variations are diverse, and data are lacking with respect to the population of Spain and methods of detection. The objective was to examine morphological patterns of variations in hepatic venous vascularization using cadaveric dissections vs.

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Background And Purpose: The first-pass effect (FPE), defined as a first-pass Expanded Treatment in Cerebral Ischaemia (eTICI) 2c/3 reperfusion, has emerged as a key metric of efficacy in mechanical thrombectomy (MT) for acute ischaemic stroke. The proximal balloon occlusion together with direct thrombus aspiration during stent retriever thrombectomy (PROTECT)-PLUS technique consists in the use of a balloon guide catheter and a combined MT approach involving contact aspiration and a stent retriever. The aim of this study is to assess the effectiveness and safety of the PROTECT-PLUS technique using distal aspiration catheters (DACs) with different inner diameters by comparing the large-bore DAC Catalyst 7 versus the use of medium-bore DACs.

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An accurate description of electron transport at a molecular level requires a precise treatment of quantum effects. These effects play a crucial role in determining the electron transport properties of single molecules, which can be challenging to simulate classically. Here we introduce a quantum algorithm to efficiently calculate electronic current through single-molecule junctions in the weak-coupling regime.

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Goyal described occlusions in M2/3, A2/3 and P2/3 as medium vessel occlusions (MeVOs); the only available controlled data of mechanical thrombectomy (MT) in MeVOs is limited to the middle cerebral artery M2 segment, suggesting that MT may be effective and safe with high functional independence and recanalization rates. The Stent retriever Assisted Vacuum-locked Extraction (SAVE) technique in mechanical thrombectomy consists of the simultaneous use of a stent retriever and a distal aspiration catheter (DAC), with the removal of both as a unit when performing the thrombectomy pass; however, so far the low-profile (0.035 inch distal inner diameter) DACs were longer (160 cm) than conventional 0.

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The excitation of vibrational modes in molecules affects the outcome of chemical reactions, for example by providing molecules with sufficient energy to overcome activation barriers. In this work, we introduce a quantum algorithm for simulating molecular vibrational excitations during vibronic transitions. We discuss how a special-purpose quantum computer can be programmed with molecular data to optimize a vibronic process such that desired modes get excited during the transition.

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Background And Purpose: Mechanical thrombectomy techniques for intracranial medium vessel occlusions (MeVOs) have evolved in recent years, although the optimal approach is still unclear. The aim of this study was to investigate the effectiveness and safety of mechanical thrombectomy in MeVOs using mini (0.017 inches microcatheter compatible) stent retrievers combined with low-profile (0.

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Gaussian Boson Samplers are photonic quantum devices with the potential to perform intractable tasks for classical systems. As with other near-term quantum technologies, an outstanding challenge is to identify specific problems of practical interest where these devices can prove useful. Here, we show that Gaussian Boson Samplers can be used to predict molecular docking configurations, a central problem for pharmaceutical drug design.

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Random point patterns are ubiquitous in nature, and statistical models such as point processes, i.e., algorithms that generate stochastic collections of points, are commonly used to simulate and interpret them.

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Objective: To study the clinical, cognitive, and radiological progression of a cohort of patients with MS, taking into account the amyloid PET with F-florbetaben analyses.

Methods: Twenty-nine patients with MS were assessed with longitudinal structural MRI and a clinical and comprehensive neuropsychological protocol, with a mean interval between assessments of 18 ± 3.31 months.

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Background: Current consensus recommends extended vascular investigation in patients with spontaneous coronary artery dissection (SCAD). We here report our experience with the use of magnetic resonance angiography (MRA) for screening extra-coronary arteriopathy in patients presenting with SCAD.

Methods: Patients presenting with SCAD in a Spanish centre underwent prospective contrast-enhanced MRA to assess the cephalic and abdominopelvic arterial territories.

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Article Synopsis
  • Finding exponential separation between quantum and classical information tasks is a significant goal in quantum research, demonstrating an advantage for quantum communication complexity.
  • The recently developed quantum switch allows for coherent superpositions of causal order, leading to new protocols that theoretically establish this exponential separation.
  • In an experiment, researchers utilized d-dimensional quantum systems (qudits) to show that a quantum communication protocol can achieve a communication complexity advantage, requiring significantly less communication than traditional causal methods.
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Background: The Paced Auditory Serial Addition Test (PASAT) is a useful cognitive test in patients with multiple sclerosis (MS), assessing sustained attention and information processing speed. However, the neural underpinnings of performance in the test are controversial. We aimed to study the neural basis of PASAT performance by using structural magnetic resonance imaging (MRI) in a series of 242 patients with MS.

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Cognitive impairment is an important feature in multiple sclerosis (MS) and has been associated to several Magnetic Resonance Imaging (MRI) markers, but especially brain atrophy. However, the relationship between specific neuropsychological tests examining several cognitive functions and brain volumes has been little explored. Furthermore, because MS frequently damage subcortical regions, it may be an interesting model to examine the role of subcortical areas in cognitive functioning.

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Boson sampling devices are a prime candidate for exhibiting quantum supremacy, yet their application for solving problems of practical interest is less well understood. Here we show that Gaussian boson sampling (GBS) can be used for dense subgraph identification. Focusing on the NP-hard densest k-subgraph problem, we find that stochastic algorithms are enhanced through GBS, which selects dense subgraphs with high probability.

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