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New designs based on S0 Lamb modes in AlN thin layer resonating structures coupled with the implementation of structural elements in SiO2, are theoretically analyzed by the Finite Element Method (FEM). This study compares the typical characteristics of different interdigital transducer (IDTs) configurations, involving either a continuous SiO2 cap layer, or structured SiO2 elements, showing their performance in the usual terms of electromechanical coupling coefficient (K2), phase velocity, and temperature coefficient of frequency (TCF), by varying structural parameters and boundary conditions. This paper shows how to reach temperature-compensated, high-performance resonator structures based on ribbon-structured SiO2 capping. The addition of a thin diamond layer can also improve the velocity and electromechanical coupling coefficient, while keeping zero TCF and increasing the solidity of the membranes. Beyond the increase in performance allowed by such resonator configurations, their inherent structure shows additional benefits in terms of passivation, which makes them particularly relevant for sensing applications in stern environments.

Abstract Background Postthrombotic syndrome (PTS) is a long‐term complication after deep vein thrombosis (DVT) and can affect quality of life (QoL). Pathogenesis is not fully understood but inadequate anticoagulant therapy with vitamin K antagonists is a known risk factor for the development of PTS. Objectives To compare the prevalence of PTS after acute DVT and the long‐term QoL following DVT between patients treated with edoxaban or warfarin. Methods We performed a long‐term follow‐up study in a subset of patients with DVT who participated in the Hokusai‐VTE trial between 2010 and 2012 (NCT00986154). Primary outcome was the prevalence of PTS, defined by the Villalta score. The secondary outcome was QoL, assessed by validated disease‐specific (VEINES‐QOL) and generic health‐related (SF‐36) questionnaires. Results Between 2017 and 2020, 316 patients were enrolled in 26 centers in eight countries, of which 168 (53%) patients had been assigned to edoxaban and 148 (47%) to warfarin during the Hokusai‐VTE trial. Clinical, demographic, and thrombus‐specific characteristics were comparable for both groups. Mean (SD) time since randomization in the Hokusai‐VTE trial was 7.0 (1.0) years. PTS was diagnosed in 85 (51%) patients treated with edoxaban and 62 (42%) patients treated with warfarin (adjusted odds ratio 1.6, 95% CI 1.0–2.6). Mean differences in QoL scores between treatment groups were not clinically relevant. Conclusion Contrary to our hypothesis, the prevalence of PTS tended to be higher in patients treated with edoxaban compared with warfarin. No differences in QoL were observed. Further research is warranted to unravel the role of anticoagulant therapy on development of PTS.

Abstract Polarization of electromagnetic waves plays an extremely important role in interaction of radiation with matter. In particular, interaction of polarized waves with ordered matter strongly depends on orientation and symmetry of vibrations of chemical bonds in crystals. In quantum technologies, the polarization of photons is considered as a “degree of freedom”, which is one of the main parameters that ensure efficient quantum computing. However, even for visible light, polarization control is in most cases separated from light emission. In this paper, we report on a new type of polarization control, implemented directly in a spintronic terahertz emitter. The principle of control, realized by a weak magnetic field at room temperature, is based on a spin-reorientation transition (SRT) in an intermetallic heterostructure TbCo2/FeCo with uniaxial in-plane magnetic anisotropy. SRT is implemented under magnetic field of variable strength but of a fixed direction, orthogonal to the easy magnetization axis. Variation of the magnetic field strength in the angular (canted) phase of the SRT causes magnetization rotation without changing its magnitude. The charge current excited by the spin-to-charge conversion is orthogonal to the magnetization. As a result, THz polarization rotates synchronously with magnetization when magnetic field strength changes. Importantly, the radiation intensity does not change in this case. Control of polarization by SRT is applicable regardless of the spintronic mechanism of the THz emission, provided that the polarization direction is determined by the magnetic moment orientation. The results obtained open the prospect for the development of the SRT approach for THz emission control.

Abstract Background Distal deep vein thrombosis (infrapopliteal DVT without proximal DVT or pulmonary embolism [PE]) generally shares the same triggering risks factors as proximal DVT. In women of childbearing age, a frequent triggering risk factor is the use of combined oral contraceptive (COC) pills. However, data on the epidemiology and long‐term outcomes of COC‐associated distal DVT are lacking. Objectives To assess the epidemiology and long‐term outcomes of COC‐associated distal DVT. Methods Using data from the OPTIMEV (Optimisation de l’Interrogatoire dans l’évaluation du risque thrombo‐Embolique Veineux [Optimization of Interrogation in the Assessment of Thromboembolic Venous Risk]) multicenter cohort study of patients with objectively confirmed venous thromboembolism (VTE) enrolled between 2004 and 2006, we assessed in nonpregnant or postpartum women aged ≤ 50 years without cancer or history of VTE (i) proportion of COC‐associated distal DVTs among women with distal DVTs and among women with COC‐associated VTEs (distal DVT, proximal DVT, or PE) and (ii) 3‐year incidence of death, bleeding, and VTE recurrence. Results COC‐associated distal DVTs (n = 54) represented 43.9% of all distal DVTs and 51.9% of COC‐associated VTEs. All but one woman with a COC‐associated distal DVT received therapeutic anticoagulation for a median of 3 months. At 3‐year follow‐up, all women with COC‐associated distal DVTs were alive, and none had bled during anticoagulant treatment or had experienced a DVT or PE recurrence after stopping anticoagulants. Similar results were found in patients with COC‐associated proximal DVT and PE: The VTE recurrence rate was 1.7% per patient‐year (PY) and 0% PY, respectively, and there were no deaths or major bleeds in either group. Conclusions Distal DVT was the most frequent clinical presentation of COC‐associated VTE and had similarly favorable long‐term outcomes as other COC‐associated VTE.

Abstract Background Long‐term sequelae of acute pulmonary embolism (PE) include decreased quality of life (QoL). Evidence suggests that adequacy of initial anticoagulant treatment in the acute phase of venous thrombosis has a key impact on late postthrombotic complications. We hypothesize that patients with acute PE treated with edoxaban for acute PE experience have improved QoL compared to those treated with warfarin. Methods Patients with PE who participated in the Hokusai‐VTE trial were contacted between June 2017 and September 2020 for a single long‐term follow‐up visit. Main outcomes were the generic and disease‐specific QoL measured by the 36‐Item Short Form Health Survey (SF‐36) and Pulmonary Embolism Quality of Life questionnaire. Results We included 251 patients from 26 centers in eight countries, of which 129 (51%) had been assigned to edoxaban and 122 (49%) to warfarin. Patient‐ and thrombus‐specific characteristics were similar in both groups. Mean time since randomization in the Hokusai‐VTE trial was 7.0 years (standard deviation, 1.0). No relevant or statistical differences were observed in the QoL for patients treated with edoxaban compared to patients treated with warfarin. The mean difference between patients treated with edoxaban and patients with PE treated with warfarin was 0.8 (95% confidence interval [CI]. −1.6 to 3.2) for the SF‐36 summary mental score and 1.6 (95% CI, −0.9 to 4.1) for summary physical score. Conclusion Our findings indicate that patients with an index PE treated with edoxaban or warfarin have a similar long‐term QoL. Since our study was a follow‐up study from a well‐controlled clinical trial setting, future studies should be designed in a daily clinical practice setting. We suggest a longitudinal design for investigation of changes in QoL over time.

Abstract Introduction VTE‐BLEED is a validated score for identification of patients at increased risk of major bleeding during extended anticoagulation for venous thromboembolism (VTE). It is unknown whether VTE‐BLEED high‐risk patients also have an increased risk for recurrent VTE, which would limit the potential usefulness of the score. Methods This was a post hoc analysis of the randomized, double‐blind, placebo‐controlled PADIS‐PE trial that randomized patients with a first unprovoked pulmonary embolism (PE) initially treated during 6 months to receive an additional 18‐month of warfarin vs. placebo. The primary outcome of this analysis was recurrent VTE during 2‐year follow‐up after anticoagulant discontinuation, that is, after the initial 6‐month treatment in the placebo arm and after 24 months of anticoagulation in the active treatment arm. This rate, adjusted for study treatment allocation, was compared between patients in the high‐ vs. low‐risk VTE‐BLEED group. Results In complete case analysis (n = 308; 82.4% of total population), 89 (28.9%) patients were classified as high risk; 44 VTE events occurred after anticoagulant discontinuation during 668 patient‐years. The cumulative incidence of recurrent VTE was 16.4% (95% confidence interval [CI], 10.0%‐26.1%; 14 events) and 14.6% (95% CI, 10.4%‐20.3%; 30 events) in the high‐risk and low‐risk VTE‐BLEED groups, respectively, for an adjusted hazard ratio of 1.16 (95% CI, 0.62‐2.19). Conclusion In this study, patients with unprovoked PE classified at high risk of major bleeding by VTE‐BLEED did not have a higher incidence of recurrent VTE after cessation of anticoagulant therapy, supporting the potential yield of the score for making management decisions on the optimal duration of anticoagulant therapy.

The need to study ultrafast processes in magnetism is due to the prospects for creating ultrafast magnetic recording and ultrafast spintronic devices. In order to excite the magnetic subsystem femtosecond optical pulses are used. The excitement is manifested as in spin precession. In metals, the material is heated first due to significant optical absorption, and significant Joule losses occur. The most important task is to search for materials in which spin processes are excited without heating. Obvious candidates are weakly absorbing materials, such as ferrite garnets. However, the range of such materials and the range of their functionality are limited.The purpose of this work is to study the dynamics of systems with nonthermal mechanisms of spin precession excitation. Such excitation is possible in ferromagnetic / antiferromagnetic heterostructures with exchange interaction, provided that the recombination time of photocarriers is shorter than the time of heat diffusion. Multilayer TbCo / FeCo structures of the near IR range were investigated for a femtosecond optical pulse. The spin dynamics are compared with the direction of the wave vector of the exciting pulse along and perpendicular to the axis of easy magnetization of the structures (“easy axis” and “hard axis” geometry, respectively). It is shown that in case of “easy axis” geometry the determinative mechanism is the thermal interaction. When the system is exposed to an excitation pulse, this mechanism leads to a decrease in the projection of magnetization on the direction of propagation of the test beam. In case of “hard axis” geometry, the magnetization turns to the magnetic field at the initial stage. Then it precesses and relaxes to an equilibrium angular orientation. Such dynamics indicate a rapid recovery of the uniaxial anisotropy field after laser irradiation. The presented results demonstrate an ultrafast change in the magnetic anisotropy induced during the fabrication of the heterostructure under study, which may be of interest for optical control of the orientation of the magnetization.

We propose a simple solid–liquid–solid triple layer biosensor platform based on bound states in the continuum (BICs) and Fano resonances to detect the acoustic properties of liquids and apply the method to a mixture of water and albumin with various concentrations. The solid–liquid–solid triple layer is composed of an epoxy as a solid layer and an albumin–water mixture as a liquid layer, and the entire system is immersed in water. In this work, we show that the structure exhibits a high sensitivity (S), quality factor (Q), and figure of merit (FOM) with a better detection limit (DL) in the vicinity of the BICs where the transmission spectra exhibit Fano resonances. The Fano resonances shift towards high frequencies as the concentration increases. The detection limit can reach very small values for a small albumin concentration (4.7%). In addition, for a given concentration and layer thickness of the sensing material, we show the effect of the incidence angle on the efficiency of the sensor in terms of the sensitivity and quality factor. The proposed structure can be designed from low-cost material and can be used as a sensor to detect different types of liquids and gases as well.

[Display omitted] This article addresses the management of venous thromboembolism in patients with malignant brain tumours, including both primary and secondary (metastatic) tumours. The available data on patients on venous thromboembolism recurrence and bleeding risks in patients with brain tumours is limited, since these patients have been excluded from most randomised, interventional, head-to-head, clinical trials comparing low molecular weight heparins to vitamin K antagonists or to direct oral Factor Xa inhibitors. More information is available from retrospective observational studies, which however were generally small, and carried a high risk of confounding. Their findings suggest that direct Factor Xa inhibitor use is associated with lower rates of intracranial haemorrhage compared with low molecular weight heparins. Overall, the safety profile of direct oral Factor Xa inhibitors when used to prevent venous thromboembolism recurrence in patients with either primary or secondary brain tumours appears to be favourable. The available data are in favour of using an anticoagulant at a full therapeutic dose in patients with primary and secondary brain tumours experiencing a venous thromboembolism, although they are not yet sufficiently robust to permit recommending a direct Factor Xa inhibitor over low-molecular weight heparin. [ABSTRACT FROM AUTHOR]

[Display omitted] Cancer is associated with a hypercoagulable state and is a well-known independent risk factor for venous thromboembolism, whereas the association between cancer and arterial thromboembolism is less well established. Arterial thromboembolism, primarily defined as myocardial infarction or stroke is significantly more frequent in patients with cancer, independently of vascular risk factors and associated with a three-fold increase in the risk of mortality. Patients with brain cancer, lung cancer, colorectal cancer and pancreatic cancer have the highest relative risk of developing arterial thromboembolism. Antithrombotic treatments should be used with caution due to the increased risk of haemorrhage, as specified in current practice guidelines. [ABSTRACT FROM AUTHOR]

Abstract Magnetoplasmonics, combining magnetic and plasmonic functions, has attracted increasing attention owing to its unique magnetic and optical properties in various nano-architectures. In this work, Ag, CoFeB and ITO layers are fabricated on anodic aluminum oxide (AAO) porous films to form hybrid multi-layered nanoporous thin films by magnetron sputtering deposition process. The designed nanostructure supports localized surface plasmon resonance (LSPR) and tunable magneto-optical (MO) activity, namely, the sign inversion, which can be controlled by AAO porous film geometry (pore diameter and inter-pore spacing) flexibly. The physical mechanism of this special MO phenomena is further analyzed and discussed by the correlation of Kerr rotation and electronic oscillations controlled by the surface plasmon resonance that is related to the nanoporous structure.

The optimal duration of anticoagulation after a first episode of unprovoked deep-vein thrombosis is uncertain. We aimed to assess the benefits and risks of an additional 18 months of treatment with warfarin versus placebo, after an initial 6 months of anticoagulation for a first unprovoked proximal deep-vein thrombosis. We conducted a multicenter, randomized, double-blind, controlled trial comparing an additional 18 months of warfarin with placebo in patients with a unprovoked proximal deep-vein thrombosis initially treated for 6 months (treatment period: 18 months; follow up after treatment period: 24 months). The primary outcome was the composite of recurrent venous thromboembolism or major bleeding at 18 months. Secondary outcomes were the composite at 42 months, as well as each component of the composite, and death unrelated to pulmonary embolism or major bleeding, at 18 and 42 months. All outcomes were centrally adjudicated. A total of 104 patients, enrolled between July 2007 and October 2013 were analyzed on an intention-to-treat basis; no patient was lost to follow-up. During the 18-month treatment period, the primary outcome occurred in none of the 50 patients in the warfarin group and in 16 out of 54 patients (cumulative risk, 29.6%) in the placebo group (hazard ratio, 0.03; 95% confidence interval: 0.01 to 0.09; P

Although diagnostic guidelines are similar, there is a huge difference in pulmonary embolism (PE) prevalence between the United States of America (US) and countries outside the USA (OUS) in the emergency care setting. In this study, we prospectively analyze patients' characteristics and differences in clinical care that may influence PE prevalence in different countries.An international multicenter prospective diagnostic study was conducted in a standard-of-care setting. Consecutive outpatients presenting to the emergency unit and suspected for PE were managed using the Wells score, STA-Liatest® D-Dimers and imaging.The prevalence of PE in the study was 7.9% in low and moderate risk patients. Among the 1060 patients with low or moderate pre-test probability (PTP), PE prevalence was four times higher in OUS (10.7%) than in the US (2.5%) (P < 0.0001). The mean number of imaging procedures performed for one new PE diagnosis was 3.3 in OUS vs 17 in the US (P < 0.001). Stopping investigation in the case of negative D-dimers (DD combined) with low/moderate PTP was more frequent in OUS (92.7%) than in the US (75.7%) (P < 0.01). Moreover, the use of imaging was much higher in the US (44.4% vs 19.2% in OUS) in the case of moderate PTP combined with negative DD.Differences between US and OUS PE prevalence in emergency setting might be explained by differences in patients' characteristics and mostly in care patterns. US physicians performed computed tomographic pulmonary angiography more often than in Europe in cases of low/moderate PTP combined with negative DD.ClinicalTrials.gov NCT01221805.