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1.
Adv Mater ; : e2403873, 2024 Jun 17.
Artigo em Inglês | MEDLINE | ID: mdl-38881289

RESUMO

Mott metal-insulator transitions possess electronic, magnetic, and structural degrees of freedom promising next-generation energy-efficient electronics. A previously unknown, hierarchically ordered, and anisotropic supercrystal state is reported and its intrinsic formation characterized in-situ during a Mott transition in a Ca2RuO4 thin film. Machine learning-assisted X-ray nanodiffraction together with cryogenic electron microscopy reveal multi-scale periodic domain formation at and below the film transition temperature (TFilm ≈ 200-250 K) and a separate anisotropic spatial structure at and above TFilm. Local resistivity measurements imply an intrinsic coupling of the supercrystal orientation to the material's anisotropic conductivity. These findings add a new degree of complexity to the physical understanding of Mott transitions, opening opportunities for designing materials with tunable electronic properties.

2.
Cureus ; 15(7): e42008, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37593318

RESUMO

Acute promyelocytic leukemia (APL) is a subgroup of acute myeloid leukemia (AML), and while not a common form of cancer, it does make up a modest portion of acute leukemia. The genetic hallmark of APL is the t(15;17)(q24.1;q21.2) promyelocytic leukemia/retinoic acid receptor alpha (PML/RARA) protein. We present the case of a patient who had undergone prior therapy for stage IIIC squamous cell carcinoma of the anorectal region with 5-fluorouracil, mitomycin C, and radiation and developed therapy-related acute promyelocytic leukemia about 18 months later. We also review the clinical features and management of APL while also highlighting that therapy-related APL, although uncommon, can develop from chemoradiation. The specific diagnosis of therapy-related APL is its own distinct diagnosis, but its treatment remains the same as primary APL.

3.
Proc Natl Acad Sci U S A ; 120(28): e2303312120, 2023 Jul 11.
Artigo em Inglês | MEDLINE | ID: mdl-37410867

RESUMO

New properties and exotic quantum phenomena can form due to periodic nanotextures, including Moire patterns, ferroic domains, and topologically protected magnetization and polarization textures. Despite the availability of powerful tools to characterize the atomic crystal structure, the visualization of nanoscale strain-modulated structural motifs remains challenging. Here, we develop nondestructive real-space imaging of periodic lattice distortions in thin epitaxial films and report an emergent periodic nanotexture in a Mott insulator. Specifically, we combine iterative phase retrieval with unsupervised machine learning to invert the diffuse scattering pattern from conventional X-ray reciprocal-space maps into real-space images of crystalline displacements. Our imaging in PbTiO3/SrTiO3 superlattices exhibiting checkerboard strain modulation substantiates published phase-field model calculations. Furthermore, the imaging of biaxially strained Mott insulator Ca2RuO4 reveals a strain-induced nanotexture comprised of nanometer-thin metallic-structure wires separated by nanometer-thin Mott-insulating-structure walls, as confirmed by cryogenic scanning transmission electron microscopy (cryo-STEM). The nanotexture in Ca2RuO4 film is induced by the metal-to-insulator transition and has not been reported in bulk crystals. We expect the phasing of diffuse X-ray scattering from thin crystalline films in combination with cryo-STEM to open a powerful avenue for discovering, visualizing, and quantifying the periodic strain-modulated structures in quantum materials.


Assuntos
Filmes Cinematográficos , Refração Ocular , Aprendizado de Máquina não Supervisionado
4.
Earth Planets Space ; 75(1): 103, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37378051

RESUMO

We created high-resolution shape models of Phobos and Deimos using stereophotoclinometry and united images from Viking Orbiter, Phobos 2, Mars Global Surveyor, Mars Express, and Mars Reconnaissance Orbiter into a single coregistered collection. The best-fit ellipsoid to the Phobos model has radii of (12.95 ± 0.04) km × (11.30 ± 0.04) km × (9.16 ± 0.03) km, with an average radius of (11.08 ± 0.04) km. The best-fit ellipsoid to the Deimos model has radii of (8.04 ± 0.08) km × (5.89 ± 0.06) km × (5.11 ± 0.05) km with an average radius of (6.27 ± 0.07) km. The new shape models offer substantial improvements in resolution over existing shape models, while remaining globally consistent with them. The Phobos model resolves grooves, craters, and other surface features ~ 100 m in size across the entire surface. The Deimos model is the first to resolve geological surface features. These models, associated data products, and a searchable, coregistered collection of images across six spacecraft are publicly available in the Small Body Mapping Tool, and will be archived with the NASA Planetary Data System. These products enable an array of future studies to advance the understanding of Phobos and Deimos, facilitate coregistration of other past and future datasets, and set the stage for planning and operating future missions to the moons, including the upcoming Martian Moons eXploration (MMX) mission. Supplementary Information: The online version contains supplementary material available at 10.1186/s40623-023-01814-7.

5.
Am J Nephrol ; 54(7-8): 329-336, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37253348

RESUMO

INTRODUCTION: Kidney stone type varies with age, sex, season, and medical conditions. Lower estimate glomerular filtration rate (eGFR) leads to changes in urine chemistry, and risk factors for kidney stones are thought to vary by stone type. We explore the association between eGFR, urine risk factors, and common stone compositions. METHODS: This was a retrospective cohort study of 811 kidney stone patients seen at Yale Medicine between 1994 and 2021 with serum chemistries and 24-h urine chemistries matched within 1 year of baseline stone analysis. Patients' eGFR was calculated using the Chronic Kidney Disease Epidemiology Collaboration (CKD-EPI) 2021 equation. Demographics and medical history were compared by χ2 tests. 24-h urine chemistries and stone analyses were analyzed by one-way ANOVA. Linear regressions were performed to control for demographics, comorbidities, and stone composition. RESULTS: With lower eGFR, the proportion of calcium stones declined while uric acid (UA) stones increased. On univariable analysis, lower eGFR was associated with lower urine pH, calcium, citrate, UA, magnesium, phosphorus, and ammonium. On multivariable analysis, controlling for age, sex, ethnicity, body mass index, comorbidities, and stone type, these factors remained significant. Stone formers with lower eGFR had elevated supersaturation for UA, but reduced supersaturations for calcium-containing stones. Though urine oxalate was significant on univariable analysis, it was not on multivariable analysis. CONCLUSION: Changes in urine parameters are strongly correlated with eGFR regardless of stone type. Renal function may play a key role in modulating kidney stone risk factors. Strategies to mitigate stone risk may need to vary with kidney function, especially when patient urine or stone composition data are unavailable.


Assuntos
Cálcio , Cálculos Renais , Humanos , Estudos Retrospectivos , Cálculos Renais/epidemiologia , Cálculos Renais/etiologia , Fatores de Risco , Rim
7.
Cureus ; 14(11): e31154, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-36483902

RESUMO

Paraneoplastic syndromes (PNS) are uncommon, distinct clinical complications of a primary tumor. Paraneoplastic cerebellar degeneration (PCD) is a PNS that is described as an autoimmune response targeting Purkinje cells in the cerebellum. Ovarian cancer (OC) is one of the most prevalent causes of cancer-related deaths in women. Anti-Yo is the most common onconeural antibody produced in the PCD immune response and is most typically found in ovarian and breast cancer patients. While the current literature highlights the predisposing genetic factors, diagnostic workflows, and treatment options, the pathophysiology of PCD, among other considerations, remains largely unestablished. This review aimed to systematically observe procedural solutions to facilitate an early diagnosis and improve the prognosis of patients with OC-associated PCD. To that end, we examined literature published from 01/01/2015-11/10/2022 indexed in PubMed by using the keywords "paraneoplastic, cerebellar degeneration" combined with "ovarian cancer." Inclusion criteria were met if PCD and OC diagnoses were made and if studies provided adequate patient information. After screening and assessing records for eligibility using the inclusion and exclusion criteria, 18 articles involving 102 patients were included. The typical patient observed in this sample was diagnosed with International Federation of Gynecology and Obstetrics (FIGO) Stage III, high-grade serous carcinoma. The diagnostic workup typically included a clinical evaluation for dysarthria (50%), ataxia (60%), and gait abnormalities (50%), along with multiple imaging modalities and serological findings (90%). Genetic screening for human leukocyte antigen (HLA) haplotype susceptibility for PCD and immune tolerance modulators regulation may also be recommended prior to starting treatment. Findings support the use of corticosteroids (35%) and intravenous immunoglobulin (IVIg) (40%) as viable treatment options for managing PCD in conjunction with systemic therapy for the primary malignancy. A diagnosis of PCD should be considered if a patient has had a malignancy in the past five years with the presence of explicit cerebellar symptoms. This clinical diagnosis can be further supplemented by serologic and radiologic findings. Recognizing PCD symptoms and scheduling genetic and proteomic testing may help with early diagnosis and better prognosis.

8.
Nano Lett ; 22(24): 10095-10101, 2022 Dec 28.
Artigo em Inglês | MEDLINE | ID: mdl-36473700

RESUMO

The Ruddlesden-Popper (An+1BnO3n+1) compounds are highly tunable materials whose functional properties can be dramatically impacted by their structural phase n. The negligible differences in formation energies for different n can produce local structural variations arising from small stoichiometric deviations. Here, we present a Python analysis platform to detect, measure, and quantify the presence of different n-phases based on atomic-resolution scanning transmission electron microscopy (STEM) images. We employ image phase analysis to identify horizontal Ruddlesden-Popper faults within the lattice images and quantify the local structure. Our semiautomated technique considers effects of finite projection thickness, limited fields of view, and lateral sampling rates. This method retains real-space distribution of layer variations allowing for spatial mapping of local n-phases to enable quantification of intergrowth occurrence and qualitative description of their distribution suitable for a wide range of layered materials.

9.
Cureus ; 14(10): e30708, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-36439610

RESUMO

Switch/sucrose non-fermentable-related, matrix-associated, actin-dependent regulator of chromatin, subfamily A, member 4-deficient undifferentiated tumor (SMARCA4-dUT) is a rare malignancy due to inactivating mutations in the SMARCA4 gene of the switch/sucrose non-fermentable (SWI/SNF) chromatin remodeling complex. These are aggressive malignancies presenting predominantly in male smokers in their fifth and sixth decades of life with nonspecific respiratory symptoms. Most patients have metastatic disease on presentation. The pattern of metastasis is similar to carcinomas, and the most common metastatic sites are lymph nodes, bones, and adrenal glands. Histologically, these tumors can be either entirely sarcomatoid or with mixed features of sarcoma and carcinoma, with extensive necrosis and high mitotic activity. Immunohistochemistry demonstrates negative expression of keratin and claudin-4, and tumor cell nuclei characteristically lack expression of Brahma-related gene-1 (BRG1). No standard treatment guidelines have been established due to the relative rarity of these tumors, and systemic chemoimmunotherapy has demonstrated benefit in some cases. We report two cases of SMARCA4-dUT with their clinical course and management to provide a perspective on the behavior of these tumors in a Western population cohort.

10.
Cureus ; 14(6): e26369, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35911355

RESUMO

Scrub typhus is a zoonotic febrile illness caused by Orientia tsutsugamushi and transmitted by Leptotrombidium larvae. Scrub typhus often presents with nonspecific clinical features, and ranges in severity from mild illness to multiorgan failure and fatality. The disease is primarily found in the Asia-Pacific rim, including India, Pakistan, Thailand, Malaysia, Korea, and China. Due to frequent limitations in healthcare resources in many of these countries, the diagnosis and management of scrub typhus meningoencephalitis pose unique challenges. This review focuses on the epidemiology, clinical features, diagnostic testing, and management modalities in such resource-limited settings. Exercising a high index of clinical suspicion and timely diagnostic tests and management strategies are vital to prevent life-threatening complications of this treatable illness.

11.
Langmuir ; 38(33): 10288-10304, 2022 08 23.
Artigo em Inglês | MEDLINE | ID: mdl-35943351

RESUMO

Microbubbles are tiny gas-filled bubbles that have a variety of applications in ultrasound imaging and therapeutic drug delivery. Microbubbles can be synthesized using a number of techniques including sonication, amalgamation, and saline shaking. These approaches can produce highly concentrated microbubble suspensions but offer minimal control over the size and polydispersity of the microbubbles. One of the simplest and effective methods for producing monodisperse microbubbles is capillary-embedded T-junction microfluidic devices, which offer great control over the microbubble size. However, lower production rates (∼200 bubbles/s) and large microbubble sizes (∼300 µm) limit the applicability of such devices for biomedical applications. To overcome the limitations of these technologies, we demonstrate in this work an alternative approach to combine a capillary-embedded T-junction device with ultrasound to enhance the generation of narrow-sized microbubbles in aqueous suspensions. Two T-junction microfluidic devices were connected in parallel and combined with an ultrasonic horn to produce lipid-coated SF6 core microbubbles in the size range of 1-8 µm. The rate of microbubble production was found to increase from 180 microbubbles/s in the absence of ultrasound to (6.5 ± 1.2) × 106 bubble/s in the presence of ultrasound (100% ultrasound amplitude). When stored in a closed environment, the microbubbles were observed to be stable for up to 30 days, with the concentration of the microbubble suspension decreasing from ∼2.81 × 109/mL to ∼2.3 × 106/mL and the size changing from 1.73 ± 0.2 to 1.45 ± 0.3 µm at the end of 30 days. The acoustic response of these microbubbles was examined using broadband attenuation spectroscopy, and flow phantom imaging was performed to determine the ability of these microbubble suspensions to enhance the contrast relative to the surrounding tissue. Overall, this approach of coupling ultrasound with microfluidic parallelization enabled the continuous production of stable microbubbles at high production rates and low polydispersity using simple T-junction devices.


Assuntos
Dispositivos Lab-On-A-Chip , Microbolhas , Acústica , Meios de Contraste/química , Suspensões , Ultrassonografia/métodos
12.
J Endourol ; 36(11): 1489-1494, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-35670255

RESUMO

Objective: To investigate if peritumor and/or intratumor vasculature is associated with high-grade tumor histology for renal cell carcinoma. Methods: A retrospective review at a tertiary care facility was performed of patients who underwent radical nephrectomy or partial nephrectomy for a renal tumor between January 2015 and December 2020. Data of tumor characteristics were collected from final pathology reports. A single radiologist specializing in genitourinary imaging reviewed all preoperative cross-sectional imaging for peritumor vessels and intratumor vessels. Single and multivariable logistic regression was utilized to identify variables associated with high-grade tumor histology. Results: The average tumor size on final pathology report was 6.4 cm (range 3.0-17.0 cm). Ninety-two patients (56.1%) had either an enlarged peritumor vessel (n = 72), an intratumor vessel (n = 3), or both a peritumor vessel and an intratumor vessel (n = 17). Of the 92 patients with either a peritumor vessel or both a peritumor vessel and intratumor vessel, 60.9% of these patients had high Fuhrman grade histology on final pathology report (60.9% vs 39.1%, p < 0.001). Pathologic stage T1a tumors with an enlarged peritumor vessel on preoperative imaging were associated with high Fuhrman grade histology (58.3% vs 41.7%, p = 0.015). Across all stages, the presence of an enlarged peritumor vessel was significantly associated with high Fuhrman grade (odds ratio: 2.37, 95% confidence interval 1.17-4.9, p = 0.01). Conclusion: Findings suggest that vessels surrounding small renal tumors and large renal tumors is associated with high tumor grade (Fuhrman grade >3). Further research is needed to support the association of peritumor vessels with high tumor grade.


Assuntos
Carcinoma de Células Renais , Neoplasias Renais , Humanos , Neoplasias Renais/diagnóstico por imagem , Neoplasias Renais/cirurgia , Neoplasias Renais/patologia , Carcinoma de Células Renais/diagnóstico por imagem , Carcinoma de Células Renais/cirurgia , Carcinoma de Células Renais/patologia , Nefrectomia , Rim/diagnóstico por imagem , Rim/cirurgia , Rim/patologia , Razão de Chances , Estudos Retrospectivos , Prognóstico
13.
BMJ Open ; 12(3): e053008, 2022 03 11.
Artigo em Inglês | MEDLINE | ID: mdl-35277401

RESUMO

OBJECTIVES: The aim of the current investigation is to estimate the incidence and risk for neurocognitive disorders (NCD) in a chronic kidney disease (CKD) cohort with diabetes, compared with an age and sex-matched control cohort. DESIGN: Longitudinal follow-up. SETTING: District general hospital North Wales, UK. PARTICIPANTS: Ninety-two patients with CKD and an age and gender-matched sample of 143 controls at baseline and at approximately 36 months. INTERVENTIONS: Cognitive function was assessed in the patients with CKD (mean age 75.8±9.1; 49 men: 43 women) and the control cohort (mean age 74.4±6.2; 71 men: 72) at baseline and at approximately 36 months. An NCD diagnosis was based on patient, informant, case note review, neuropsychological assessment and application of Diagnostic and Statistical Manual of Mental disorders V.5 (DSM-5) for an NCD and Petersen's criteria for mild cognitive impairment. RESULTS: Follow-up neuropsychological assessment and application of DSM-5 criteria of the cognitively normal patients and controls revealed, 25/92 (27%) of the CDK and 20/143 (13.9%) in the control cohort developed an NCD. The CKD cohort had a twofold increased risk for the development of an NCD compared with the controls, adjusted for age and sex. The incidence rate for an NCD in the CKD cohort was 10.5 and 5.1 in the controls, respectively. No association was observed with the stage of CKD and cognitive function. CONCLUSIONS: This longitudinal investigation found that patients with CKD have a twofold increased risk for the development of an NCD. The current investigation highlighted the need to recognise that NCD in patients with CKD is a common comorbidity and that they are at a much higher risk for the development of a significant neurodegenerative disorders. In view of these risks, neuropsychological screening and assessment should be incorporated into normal CKD clinical practice and management.


Assuntos
Disfunção Cognitiva , Diabetes Mellitus , Insuficiência Renal Crônica , Idoso , Idoso de 80 Anos ou mais , Disfunção Cognitiva/diagnóstico , Disfunção Cognitiva/epidemiologia , Disfunção Cognitiva/etiologia , Estudos de Coortes , Diabetes Mellitus/epidemiologia , Feminino , Humanos , Incidência , Estudos Longitudinais , Masculino , Insuficiência Renal Crônica/complicações , Insuficiência Renal Crônica/epidemiologia , Fatores de Risco , País de Gales/epidemiologia
14.
Urology ; 165: 275-279, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-35063465

RESUMO

OBJECTIVE: To compare operative efficiency of Holmium laser enucleation of the prostate (HoLEP) using both the standard multi-incisional approach and en-bloc enucleation with early apical release during the initial learning curve. MATERIALS AND METHODS: We retrospectively reviewed the initial 95 consecutive men who underwent HoLEP between April 2019 and September 2020 by a single surgeon. We compared patient demographics, and pre-, intra-, and post-operative metrics between both groups. Differences between groups were evaluated with Mann-Whitney U and Kruskal-Wallis tests. RESULTS: Forty-nine patients underwent the standard HoLEP approach, and 46 patients underwent the en-bloc approach. Compared to a standard HoLEP, the en-bloc approach was associated with decreased operative time (131.11 minutes vs 153.59 minutes, P = .007) with similar weights of tissue removed. Operative efficiency, as measured by grams of prostate tissue removed per minute, was greater for the en-bloc approach (0.49 g/min vs 0.36 g/min, P = .005). There was no difference in length of stay (0.91 days vs 0.96 days, P = .383), laser efficiency (4.41 kJ/g vs 4.83 kJ/g, P = .200), or number of post-operative complications (10 vs 6, P = .236) between the groups. CONCLUSION: Utilization of the en-bloc technique during the initial learning curve allows for a faster, more efficient operation without any difference in functional outcomes or major complications compared to a standard HoLEP.


Assuntos
Terapia a Laser , Lasers de Estado Sólido , Hiperplasia Prostática , Cirurgiões , Hólmio , Humanos , Terapia a Laser/métodos , Lasers de Estado Sólido/uso terapêutico , Curva de Aprendizado , Masculino , Projetos Piloto , Próstata/cirurgia , Hiperplasia Prostática/cirurgia , Estudos Retrospectivos , Resultado do Tratamento
15.
Adv Mater ; 34(12): e2106728, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-35064593

RESUMO

The search of novel quasi-1D materials is one of the important aspects in the field of material science. Toroidal moment, the order parameter of ferrotoroidic order, can be generated by a head-to-tail configuration of magnetic moment. It has been theoretically proposed that 1D dimerized and antiferromagnetic (AFM)-like spin chain hosts ferrotoroidicity and has the toroidal moment composed of only two antiparallel spins. Here, the authors report a ferrotoroidic candidate of Ba6 Cr2 S10 with such a theoretical model of spin chain. The structure consists of unique dimerized face-sharing CrS6 octahedral chains along the c axis. An AFM-like ordering at ≈10 K breaks both space- and time-reversal symmetries and the magnetic point group of mm'2'allows three ferroic orders in Ba6 Cr2 S10 : (anti)ferromagnetic, ferroelectric, and ferrotoroidic orders. Their investigation reveals that Ba6 Cr2 S10 is a rare ferrotoroid ic candidate with quasi 1D spin chain, which can be considered as a starting point for the further exploration of the physics and applications of ferrotoroidicity.

16.
Earth Planets Space ; 73(1): 217, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34970072

RESUMO

The MEGANE instrument onboard the MMX mission will acquire gamma-ray and neutron spectroscopy data of Phobos to determine the elemental composition of the martian moon and provide key constraints on its origin. To produce accurate compositional results, the irregular shape of Phobos and its proximity to Mars must be taken into account during the analysis of MEGANE data. The MEGANE team is adapting the Small Body Mapping Tool (SBMT) to handle gamma-ray and neutron spectroscopy investigations, building on the demonstrated record of success of the SBMT being applied to scientific investigations on other spacecraft missions of irregularly shaped bodies. This is the first application of the SBMT to a gamma-ray and neutron spectroscopy dataset, and the native, three-dimensional foundation of the SBMT is well suited to MEGANE's needs. In addition, the SBMT will enable comparisons between the MEGANE datasets and other datasets of the martian moons, including data from previous spacecraft missions and MMX's multi-instrument suite.

17.
Cureus ; 13(10): e18930, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34812314

RESUMO

Hematologic paraneoplastic syndromes with extreme neutrophilia and eosinophilia are very rarely associated with adenocarcinoma of the lung. We describe a case of a 57-year-old female who presented with neutrophil- and eosinophil-predominant hyperleukocytosis and hypoxic respiratory insufficiency. Bone marrow biopsy confirmed metastatic adenocarcinoma, similar to the biopsy-proven adenocarcinoma of the lung. She was administered one dose of cytotoxic chemotherapy with carboplatin and pemetrexed and started on leukoreductive therapy with hydroxyurea. Molecular testing revealed a BRAF V600E mutation and she was started on dabrafenib and trametinib with significant clinical improvement. This is the first reported case of metastatic BRAF V600E mutated non-small cell lung cancer presenting with extreme neutrophilia and eosinophilia treated with a combination BRAF and mitogen-activated extracellular kinase (MEK) inhibitor.

19.
Proc Natl Acad Sci U S A ; 117(20): 10654-10659, 2020 May 19.
Artigo em Inglês | MEDLINE | ID: mdl-32366660

RESUMO

We have measured the angle-resolved transverse resistivity (ARTR), a sensitive indicator of electronic anisotropy, in high-quality thin films of the unconventional superconductor Sr2RuO4 grown on various substrates. The ARTR signal, heralding the electronic nematicity or a large nematic susceptibility, is present and substantial already at room temperature and grows by an order of magnitude upon cooling down to 4 K. In Sr2RuO4 films deposited on tetragonal substrates the highest-conductivity direction does not coincide with any crystallographic axis. In films deposited on orthorhombic substrates it tends to align with the shorter axis; however, the magnitude of the anisotropy stays the same despite the large lattice distortion. These are strong indications of actual or incipient electronic nematicity in Sr2RuO4.

20.
ACS Appl Mater Interfaces ; 12(18): 20691-20703, 2020 May 06.
Artigo em Inglês | MEDLINE | ID: mdl-32292024

RESUMO

We study the interplay between epitaxial strain, film thickness, and electric field in the creation, modification, and design of distinct ferroelastic structures in PbTiO3 thin films. Strain and thickness greatly affect the structures formed, providing a two-variable parameterization of the resulting self-assembly. Under applied electric fields, these strain-engineered ferroelastic structures are highly malleable, especially when a/c and a1/a2 superdomains coexist. To reconfigure the ferroelastic structures and achieve self-assembled nanoscale-ordered morphologies, pure ferroelectric switching of individual c-domains within the a/c superdomains is essential. The stability, however, of the electrically written ferroelastic structures is in most cases ephemeral; the speed of the relaxation process depends sensitively on strain and thickness. Only under low tensile strain-as is the case for PbTiO3 on GdScO3-and below a critical thickness do the electrically created a/c superdomain structures become stable for days or longer, making them relevant for reconfigurable nanoscale electronics or nonvolatile electromechanical applications.

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