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1.
Front Ophthalmol (Lausanne) ; 4: 1388197, 2024.
Article in English | MEDLINE | ID: mdl-38984143

ABSTRACT

Purpose: To evaluate percutaneous triamcinolone (TA) injection efficacy in treating upper eyelid retraction (UER) for Australian thyroid eye disease (TED) patients. Methods: We conducted a retrospective analysis across 8 years and multiple diverse Australian centres identified UER patients who received TA injections. A single operator administered 40mg/1ml TA through upper eyelid skin. Assessments at 4-6 weeks and subsequent eyelid measurements gauged treatment response and complications. Results: 24 patients and 25 eyelids were included in the study. 91.6% were female, mean age 40.8 ± 10.3 years with mean follow-up of 17.5 months (± 18.5). Pre-treatment MRD1 was 6.2mm ± 1.4, and we observed a mean improvement of 2.2mm from pre-treatment to post-treatment (p<0.001). The mean UER measurement before treatment (defined as MRD1 - 4.0mm) was 3.0mm ± 1.3 (range, 0-6mm). After treatment, the mean UER measurement was -0.1mm. Quality of life (QOL) assessment improved significantly, from pre-treatment score of 4.13 ± 2.4 to post-treatment 8.0 ±1.7 (p<0.001). Conclusions: Percutaneous injection of TA is an effective and safe treatment option for UER in patients with TED. This technique can be performed without upper eyelid eversion, which makes it more tolerable for patients and less complex for the operator compared to the transconjunctival injection approach. Our results show a significant improvement in MRD1 and UER, as well as patient QOL. Moreover, we found a low rate of complications (4.2% induced ptosis) and no cases of raised intraocular pressure. Percutaneous TA injection can greatly reduce the need for eyelid lowering surgery in this patient population.

2.
J Phys Condens Matter ; 36(40)2024 Jul 09.
Article in English | MEDLINE | ID: mdl-38979851

ABSTRACT

In this study, we employ density functional theory based first-principles calculations to investigate the spin-orbit effects in the electronic structure of a polar-nonpolar sandwich heterostructure namelyLaAlO3/SrTiO3/LaAlO3. Our focus on theTi-3dbands reveals an inverted ordering of theSrTiO3-t2gorbital near the n-type interface, which is consistent with earlier experimental work. In contrast, toward the p-type interface, the orbital ordering aligns with the natural ordering ofSrTiO3orbitals, influenced by crystal field splitting. In the presence of SOC, a notable inter-orbital coupling betweent2gandegorbitals is observed within the tetragonal slab, a phenomenon not reported before in theSrTiO3-based 2D systems. Additionally, our observations highlight that the cubic Rashba splitting in this system surpasses the linear Rashba splitting, contrary to experimental findings. This comprehensive analysis contributes to a refined understanding of the role of orbital mixing in Rashba splitting in the sandwich oxide heterostructures.

3.
Article in English | MEDLINE | ID: mdl-38981585

ABSTRACT

Delving into the intricate interplay between spin-orbit coupling and Coulomb correlations in strongly correlated oxides, particularly perovskite compounds, has unveiled a rich landscape of exotic phenomena ranging from unconventional superconductivity to the emergence of topological phases. In this study, we have employed pulsed laser deposition (PLD) technique to grow SrIrO3 (SIO) thin films on SrTiO3 substrates, systematically varying the oxygen content during the post-deposition annealing. X-ray Photoelectron Spectroscopy (XPS) provided insights into the stoichiometry and spin-orbit splitting energy of Iridium within the SIO film, while high-resolution X-ray studies meticulously examined the structural integrity of the thin films. Remarkably, our findings indicate a decrease in the metallicity of SIO thin films with reduced annealing O2 partial pressure. Furthermore, we carried out magneto-transport studies on the SIO thin films, the results revealed intriguing insights into spin transport as a function of oxygen content. The tunability of the electronic band structure of SrIrO3 films with varying oxygen vacancy is correlated with the DFT calculations. Our findings elucidate the intricate mechanisms dictating spin transport properties in SrIrO3 thin films, offering invaluable guidance for the design and optimization of spintronic devices based on complex oxide materials. Notably, the ability to tune bandwidth by varying post-annealing oxygen partial pressure in iridate-based spintronic materials holds significant promise for advancing technological applications in the spintronics domain. .

4.
Adv Sci (Weinh) ; : e2403648, 2024 Jul 10.
Article in English | MEDLINE | ID: mdl-38984445

ABSTRACT

Antiferromagnets are competitive candidates for the next generation of spintronic devices owing to their superiority in small-scale and low-power-consumption devices. The electrical manipulation of the magnetization and exchange bias (EB) driven by spin-orbit torque (SOT) in ferromagnetic (FM)/antiferromagnetic (AFM) systems has become focused in spintronics. Here, the realization of a large perpendicular EB field in Co/IrMn and the effective manipulation of the magnetic moments of the magnetic Co layer and EB field by SOT in Pt/Co/IrMn system is reported. During the SOT-driven switching process, an asymmetrically manipulated state is observed. Current pulses with the same amplitude but opposite directions induce different magnetization states. Magneto-optical Kerr measurements reveal that this is due to the coexistence of stable and metastable antiferromagnetic domains in the AFM. Exploiting the asymmetric properties of these FM/AFM structures, five spin logic gates, namely AND, OR, NOR, NAND, and NOT, are realized in a single cell via SOT. This study provides an insight into the special ability of SOT on AFMs and also paves an avenue to construct the logic-in-memory and neuromorphic computing cells based on the AFM spintronic system.

5.
Orbit ; : 1-6, 2024 Jul 08.
Article in English | MEDLINE | ID: mdl-38976616

ABSTRACT

This case report highlights a unique presentation of Erdheim-Chester Disease (ECD) with bilateral scleral lesions, choroidal infiltration, and extensive sinus involvement. It is the first case report where the diagnosis was confirmed through a scleral biopsy after an initial presentation of a unilateral nodular scleritis. There was a gradual disease progression and ocular examination later revealed bilateral subconjunctival hyperemic lesions and mild exophthalmos, ophthalmoplegia, and extensive choroidal infiltration. Infiltration of the frontal and maxillary sinus was present and extended into the nasal cavity and both orbits. The diagnostic work-up is described in detail. Current treatment options are analyzed. It is emphasized that the ophthalmologist can play a crucial role in the diagnosis of ECD, given the substantial prevalence of orbital and ocular symptoms. The overall prognosis for ECD remains unfavorable, particularly in cases with orbital involvement. This case underscores the complexity and importance of a multidisciplinary approach in managing ECD.

6.
Article in English | MEDLINE | ID: mdl-38976987

ABSTRACT

The study of phonon dynamics and its interplay with magnetic ordering is crucial for understanding the unique quantum phases in the pyrochlore iridates. Here, through inelastic X-ray scattering on a single crystal sample of the pyrochlore iridate Eu2Ir2O7, we map out the phonon excitation spectra in Eu2Ir2O7 and compare them with the theoretical phonon spectra calculated using the density functional theory. Possible phonon renormalization across the magnetic long-range order transition is observed in our experiments, which is consistent with the results of the previous Raman scattering experiments.

7.
Nano Lett ; 2024 Jul 11.
Article in English | MEDLINE | ID: mdl-38989866

ABSTRACT

Two-dimensional magnet CrI3 is a promising candidate for spintronic devices. Using nonadiabatic molecular dynamics and noncollinear spin time-dependent density functional theory, we investigated hole spin relaxation in two-dimensional CrI3 and its dependence on magnetic configurations, impacted by spin-orbit and electron-phonon interactions. Driven by in-plane and out-of-plane iodine motions, the relaxation rates vary, extending from over half a picosecond in ferromagnetic systems to tens of femtoseconds in certain antiferromagnetic states due to significant spin fluctuations, associated with the nonadiabatic spin-flip in tuning to the adiabatic flip. Antiferromagnetic CrI3 with staggered layer magnetic order notably accelerates adiabatic spin-flip due to enhanced state degeneracy and additional phonon modes. Ferrimagnetic CrI3 shows a transitional behavior between ferromagnetic and antiferromagnetic types as the magnetic moment changes. These insights into the spin dynamics of CrI3 underscore its potential for rapid-response spintronic applications and advance our understanding of two-dimensional materials for spintronics.

8.
Saudi J Ophthalmol ; 38(2): 185-187, 2024.
Article in English | MEDLINE | ID: mdl-38988781

ABSTRACT

Orbital manifestations are rarely observed in multiple myeloma (MM) and when they occur, they are often the first manifestation. We report a rare occurrence of vision loss in a 51-year-old female from orbital metastases in MM without proptosis or diplopia. The ophthalmic presentation of MM is usually progressive proptosis, pain, diplopia, and visual loss. The presence of metastasis in MM indicates poor prognosis and orbital metastases have worse survival rates. In conclusion, in cases of profound vision loss with no obvious cause, neuroimaging should be performed to evaluate the orbital extent of the disease and exclude intracranial pathology.

9.
Article in English | MEDLINE | ID: mdl-38959901

ABSTRACT

While the recent prediction and observation of magnetic skyrmions bears inspiring promise for next-generation spintronic devices, how to detect and track their position becomes an important issue. In this work, we investigate the spin transport in a two-dimensional magnetic nanoribbon with the Hall-bar geometry in the presence of Rashba spin-orbit coupling and magnetic skyrmions. We employ the Kwant tight-binding code to compute the Hall conductance and local spin-polarized current density. We consider two versions of the model: One with single skyrmion and one with two separate skyrmions. It is found that the size and position of the skyrmions strongly modulate the Hall conductance near the Hall-bar position. The geometry of the Hall bar also has a strong influence on the Hall conductance of the system. With the decreasing of the width of Hall leads, the peak of Hall conductance becomes sharper. We also show the spatial distribution of the spin-polarized current density around a skyrmion located at different positions. We extend this study toward two separate skyrmions, where the Hall conductance also reveals a sizable dependence on the position of the skyrmions and their distance. Our numerical analysis offers the possibility of electrically detecting the skyrmion position, which could have potential applications in ultrahigh-density storage design.

10.
Sci Rep ; 14(1): 15294, 2024 Jul 03.
Article in English | MEDLINE | ID: mdl-38961120

ABSTRACT

Reliability mapping of 5G low orbit constellation network slice is an important means to ensure link network communication. The problem of state space explosion is a typical problem. The deep reinforcement learning method is introduced. Under the 5G low orbit constellation integrated network architecture based on software definition network (SDN) and network function virtualization (NFV), the resource requirements and resource constraints of the virtual network function (VNF) are comprehensively considered to build the 5G low orbit constellation network slice reliability mapping model, and the reliability mapping model parameters are trained and learned by using deep reinforcement learning, solve the problem of state space explosion in the reliability mapping process of 5G low orbit constellation network slices. In addition, node backup and link backup strategies based on importance are adopted to solve the problem that VNF/link reliability is difficult to meet in the reliability mapping process of 5G low orbit constellation network slice. The experimental results show that this method improves the network throughput, packet loss rate and intra slice traffic of 5G low orbit constellation, and can completely repair network faults within 0.3 s; For different number of 5G low orbit constellation network slicing requests, the reliability of this method remains above 98%; For SFC with different lengths, the average network delay of this method is less than 0.15 s.

11.
Sensors (Basel) ; 24(11)2024 May 25.
Article in English | MEDLINE | ID: mdl-38894201

ABSTRACT

Information-Centric Networking (ICN) is the emerging next-generation internet paradigm. The Low Earth Orbit (LEO) satellite mega-constellation based on ICN can achieve seamless global coverage and provide excellent support for Internet of Things (IoT) services. Additionally, in-network caching, typically characteristic of ICN, plays a paramount role in network performance. Therefore, the in-network caching policy is one of the hotspot problems. Especially, compared to caching traditional internet content, in-networking caching IoT content is more challenging, since the IoT content lifetime is small and transient. In this paper, firstly, the framework of the LEO satellite mega-constellation Information-Centric Networking for IoT (LEO-SMC-ICN-IoT) is proposed. Then, introducing the concept of "viscosity", the proposed Caching Algorithm based on the Random Forest (CARF) policy of satellite nodes combines both content popularity prediction and satellite nodes location prediction, for achieving good cache matching between the satellite nodes and content. And using the matching rule, the Random Forest (RF) algorithm is adopted to predict the matching relationship among satellite nodes and content for guiding the deployment of caches. Especially, the content is cached in advance at the future satellite to maintain communication with the current ground segment at the time of satellite switchover. Additionally, the policy considers both the IoT content lifetime and the freshness. Finally, a simulation platform with LEO satellite mega-constellation based on ICN is developed in Network Simulator 3 (NS-3). The simulation results show that the proposed caching policy compared with the Leave Copy Everywhere (LCE), the opportunistic (OPP), the Leave Copy down (LCD), and the probabilistic algorithm which caches each content with probability 0.5 (prob 0.5) yield a significant performance improvement, such as the average number of hops, i.e., delay, cache hit rate, and throughput.

12.
Sensors (Basel) ; 24(11)2024 Jun 06.
Article in English | MEDLINE | ID: mdl-38894488

ABSTRACT

Aiming to address the chicken-and-egg problem in star identification and the intrinsic parameter determination processes of on-orbit star sensors, this study proposes an on-orbit self-calibration method for star sensors that does not depend on star identification. First, the self-calibration equations of a star sensor are derived based on the invariance of the interstar angle of a star pair between image frames, without any requirements for the true value of the interstar angle of the star pair. Then, a constant constraint of the optical path from the star spot to the center of the star sensor optical system is defined to reduce the biased estimation in self-calibration. Finally, a scaled nonlinear least square method is developed to solve the self-calibration equations, thus accelerating iteration convergence. Our simulation and analysis results show that the bias of the focal length estimation in on-orbit self-calibration with a constraint is two orders of magnitude smaller than that in on-orbit self-calibration without a constraint. In addition, it is shown that convergence can be achieved in 10 iterations when the scaled nonlinear least square method is used to solve the self-calibration equations. The calibrated intrinsic parameters obtained by the proposed method can be directly used in traditional star map identification methods.

13.
ACS Appl Mater Interfaces ; 16(24): 31438-31446, 2024 Jun 19.
Article in English | MEDLINE | ID: mdl-38843313

ABSTRACT

Spin-orbit torque (SOT) has emerged as an effective means of manipulating magnetization. However, the current energy efficiency of SOT operation is inefficient due to low damping-like SOT efficiency per unit current bias. In this work, we dope conventional rare earth oxides, GdOy, into highly conductive platinum by magnetron sputtering to form a new group of spin Hall materials. A large damping-like spin-orbit torque (DL-SOT) efficiency of about 0.35 ± 0.013 is obtained in Pt0.70(GdOy)0.30 measured by the spin-torque ferromagnetic resonance (ST-FMR) technique, which is about five times that of pure Pt under the same conditions. The substantial enhancement of the spin Hall effect is revealed by theoretical analysis to be attributed to the strong side jump induced by the rare earth oxide GdOy impurities. Moreover, this large DL-SOT efficiency contributes to a low critical switching current density (8.0 × 106 A·cm-2 in the Pt0.70(GdOy)0.30 layer) in current-induced magnetization switching measurements. This systematic study on SOT switching properties suggests that Pt1-x(GdOy)x is an attractive spin current source with large DL-SOT efficiency for future SOT applications and provides another idea to regulate the spin Hall angle.

14.
Nanotechnology ; 35(36)2024 Jun 21.
Article in English | MEDLINE | ID: mdl-38861984

ABSTRACT

Electric field control of spin-orbit torque (SOT) exhibits promising potential in advanced spintronic devices through interfacial modulation. In this work, we investigate the influence of electric field and interfacial oxidation on SOT efficiency in annealed Ta/CoFeB/HfOxheterostructures. By varying annealing temperatures, the damping-like SOT efficiency reaches its peak at the annealing temperature of 320 °C, with an 80% field-free magnetization switching ratio induced by SOT having been demonstrated. This enhancement is ascribed to the annealing-induced modulation of oxygen ion migration at the CoFeB/HfOxinterface. By applying voltages across the Ta/CoFeB/HfOxheterostructures, which drives the O2‒migration across the interface, a reversible, bipolar, and non-volatile modulation of SOT efficiency was observed. The collective influence of annealing temperature and electric field effects on SOT carried out in this work provides an effective approach into facilitating the optimization and control of SOT in spintronic devices.

15.
BMJ Open Ophthalmol ; 9(1)2024 Jun 17.
Article in English | MEDLINE | ID: mdl-38886120

ABSTRACT

BACKGROUND: Graves' ophthalmopathy is a complex autoimmune disorder that can significantly affect quality of life (QoL), vision and physical appearance. Recently, a deeper understanding of the underlying pathogenesis has led to the development of novel treatment options. AIMS: The purpose of this review is to explore the current literature on conventional and novel treatment modalities and to evaluate which interventions provide the most favourable psychological and clinical outcomes in patients with moderate to severe, active Grave's ophthalmopathy. For example, QoL is an important psychosocial outcome of disease management. However, available literature demonstrates that not all clinically effective treatment options improve patients' QoL. METHODS: A systematic literature review was conducted to assess the clinical and psychosocial outcomes of different therapies for Graves' ophthalmopathy. An extensive database search of Ovid Medline, Ovid Embase and Cochrane Central Register of Controlled Trials was conducted. Studies generated were reviewed and the relevant selected data were retrieved and analysed. RESULTS: Results showed intravenous steroids, rituximab (RTX), tocilizumab and teprotumumab were all significantly effective in improving Clinical Activity Scores. Orbital radiotherapy showed a slight improvement in proptosis and diplopia. All interventions were safe with few serious adverse events being reported across all studies. All treatment modalities demonstrated beneficial improvements in both components of the Graves' Ophthalmopathy-QoL (QoL) questionnaire, apart from orbital radiotherapy which only demonstrated improvements in the visual functioning subscale. Teprotumumab was identified to be the most effective intervention for improving both clinical and psychosocial outcomes. However, further research needs to be conducted to evaluate its side effect profile and cost-effectiveness. Nonetheless, with time it has the potential to be a first-line treatment option in the management of active moderate to severe Graves' ophthalmopathy.


Subject(s)
Graves Ophthalmopathy , Quality of Life , Humans , Graves Ophthalmopathy/therapy , Graves Ophthalmopathy/psychology , Antibodies, Monoclonal, Humanized/therapeutic use , Rituximab/therapeutic use , Immunologic Factors/therapeutic use , Glucocorticoids/therapeutic use
16.
Article in English | MEDLINE | ID: mdl-38876957

ABSTRACT

The orbital cavity is a subject of interest for various specialists, and achieving optimal outcomes requires comprehensive, multidisciplinary management. This study aims to report 10 years of experience in the preoperative, surgical, and postoperative care of patients with orbital lesions, examining their clinical, radiological, and anatomopathological features and outcomes. A retrospective review of 125 patients who underwent surgical treatment for intraorbital masses between January 2012 and December 2021 was performed. Outcome measures included postoperative diplopia, exophthalmos, decimal visual acuity, eyeball position, ocular motility, operative time, complications, and aesthetic results. A total of 107 patients were included. All cases were discussed with a neuroradiologist to determine the best therapeutic approach based on preoperative imaging. Preoperative diplopia was linked to extraconal (p = 0.03) and anterior (p = 0.001) lesions, and exophthalmos and visual acuity deterioration were associated with intraconal (p = 0.02; p = 0.03) and retrobulbar (p = 0.001; p = 0.02) lesions. Complications (11.2%) included diplopia, worsened visual acuity, postoperative blepharoptosis, and postoperative ectropion. Of the patients, 80.4% reported an "excellent" aesthetic outcome. This study underscores the importance of a multidisciplinary approach based on a thorough analysis of preoperative imaging. Periorbital approaches tailored to the lesion's three-dimensional location enables safe access to most intraorbital lesions, resulting in minimal complications and good aesthetic results.

17.
Nano Lett ; 2024 Jun 10.
Article in English | MEDLINE | ID: mdl-38856112

ABSTRACT

Electrical manipulation of magnetic states in two-dimensional ferromagnetic systems is crucial in information storage and low-dimensional spintronics. Spin-orbit torque presents a rapid and energy-efficient method for electrical control of the magnetization. In this letter, we demonstrate a wafer-scale spin-orbit torque switching of two-dimensional ferromagnetic states. Using molecular beam epitaxy, we fabricate two-dimensional heterostructures composed of low crystal-symmetry WTe2 and ferromagnet CrTe2 with perpendicular anisotropy. By utilizing out-of-plane spins generated from WTe2, we achieve field-free switching of the CrTe2 perpendicular magnetization. The threshold switching current density in CrTe2/WTe2 is 1.2 × 106 A/cm2, 20 times smaller than that of the CrTe2/Pt control sample even with an external magnetic field. In addition, the switching behavior can be modulated by external magnetic fields and crystal symmetry. Our findings demonstrate a controllable and all-electric manipulation of perpendicular magnetization in a two-dimensional ferromagnet, representing a significant advancement toward the practical implementation of low-dimensional spintronic devices.

18.
Nano Lett ; 24(23): 7134-7141, 2024 Jun 12.
Article in English | MEDLINE | ID: mdl-38828962

ABSTRACT

The coexistence of superconductivity and ferromagnetism is a long-standing issue in superconductivity due to the antagonistic nature of these two ordered states. Experimentally identifying and characterizing novel heterointerface superconductors that coexist with magnetism presents significant challenges. Here, we report the observation of two-dimensional long-range ferromagnetic order in a KTaO3 heterointerface superconductor, showing the coexistence of superconductivity and ferromagnetism. Remarkably, our direct current superconducting quantum interference device measurements reveal an in-plane magnetization hysteresis loop persisting above room temperature. Moreover, first-principles calculations and X-ray magnetic circular dichroism measurements provide decisive insights into the origin of the observed robust ferromagnetism, attributing it to oxygen vacancies that localize electrons in nearby Ta 5d states. Our findings suggest KTaO3 heterointerfaces as time-reversal symmetry breaking superconductors, injecting fresh momentum into the exploration of the intricate interplay between superconductivity and magnetism enhanced by the strong spin-orbit coupling inherent to the heavy Ta in 5d orbitals.

19.
Adv Mater ; : e2313059, 2024 Jun 13.
Article in English | MEDLINE | ID: mdl-38871341

ABSTRACT

Artificial moiré superlattices created by stacking 2D crystals have emerged as a powerful platform with unprecedented material-engineering capabilities. While moiré superlattices are reported to host a number of novel quantum states, their potential for spintronic applications remains largely unexplored. Here, the effective manipulation of spin-orbit torque (SOT) is demonstrated using moiré superlattices in ferromagnetic devices comprised of twisted WS2/WS2 homobilayer (t-WS2) and CoFe/Pt thin films by altering twisting angle (θ) and gate voltage. Notably, a substantial enhancement of up to 44.5% is observed in SOT conductivity at θ ≈ 8.3°. Furthermore, compared to the WS2 monolayer and untwisted WS2/WS2 bilayers, the moiré superlattices in t-WS2 enable a greater gate-voltage tunability of SOT conductivity. These results are related to the generation of the interfacial moiré magnetic field by the real-space Berry phase in moiré superlattices, which modulates the absorption of the spin-Hall current arising from Pt through the magnetic proximity effect. This study highlights the moiré physics as a new building block for designing enhanced spintronic devices.

20.
ACS Nano ; 18(24): 15716-15728, 2024 Jun 18.
Article in English | MEDLINE | ID: mdl-38847339

ABSTRACT

Epitaxial graphene/ferromagnetic metal (Gr/FM) heterostructures deposited onto heavy metals have been proposed for the realization of spintronic devices because of their perpendicular magnetic anisotropy and sizable Dzyaloshinskii-Moriya interaction (DMI), allowing for both enhanced thermal stability and stabilization of chiral spin textures. However, establishing routes toward this goal requires the fundamental understanding of the microscopic origin of their unusual properties. Here, we elucidate the nature of the induced spin-orbit coupling (SOC) at Gr/Co interfaces on Ir. Through spin- and angle-resolved photoemission spectroscopy along with density functional theory, we show that the interaction of the heavy metals with the Gr layer via hybridization with the FM is the source of strong SOC in the Gr layer. Furthermore, our studies on ultrathin Co films underneath Gr reveal an energy splitting of ∼100 meV for in-plane and negligible for out-of-plane spin polarized Gr π-bands, consistent with a Rashba-SOC at the Gr/Co interface, which is either the fingerprint or the origin of the DMI. This mechanism vanishes at large Co thicknesses, where neither in-plane nor out-of-plane spin-orbit splitting is observed, indicating that Gr π-states are electronically decoupled from the heavy metal. The present findings are important for future applications of Gr-based heterostructures in spintronic devices.

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