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1.
Jpn J Ophthalmol ; 68(3): 216-224, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38598145

RESUMO

PURPOSE: We introduce selective internal limiting membrane (ILM) peeling, a guideline procedure to determine whether to remove the ILM during vitrectomy for rhegmatogenous retinal detachment (RRD). STUDY DESIGN: Retrospective case series METHODS: Patients who underwent pars plana vitrectomy for RRD and were followed up for 12 months or longer were included. When vitreous cortex remnants (VCRs) were detected with triamcinolone acetonide, the ILM was removed; otherwise, the ILM was preserved ("selective ILM peeling"). The factors associated with the presence of VCRs and incidence of secondary epiretinal membrane (ERM) were analyzed. RESULTS: VCRs were detected in 87 of 133 eyes (65.4%) in which the ILM was removed. Younger age, better preoperative visual acuity, and vitreous hemorrhage were negatively correlated with the presence of VCRs. No ERM occurred in the eyes after ILM peeling. Among the eyes with ILM preservation, subclinical ERM was noticed in 4 eyes (8.7%), and 1 eye (2.1%) required additional surgery owing to ERM. ERM occurred more commonly in eyes with the ILM preserved (P = .004). However, no differences in the rate of additional surgeries were found between the 2 groups. CONCLUSION: Selective ILM peeling offers an alternative option to reduce the burden of ILM peeling or additional surgery.


Assuntos
Membrana Basal , Membrana Epirretiniana , Descolamento Retiniano , Tomografia de Coerência Óptica , Acuidade Visual , Vitrectomia , Humanos , Vitrectomia/métodos , Estudos Retrospectivos , Descolamento Retiniano/cirurgia , Descolamento Retiniano/diagnóstico , Descolamento Retiniano/prevenção & controle , Descolamento Retiniano/etiologia , Membrana Epirretiniana/cirurgia , Membrana Epirretiniana/diagnóstico , Feminino , Masculino , Pessoa de Meia-Idade , Membrana Basal/cirurgia , Idoso , Seguimentos , Complicações Pós-Operatórias/prevenção & controle , Adulto , Idoso de 80 Anos ou mais
2.
Ophthalmic Epidemiol ; : 1-8, 2024 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-38507597

RESUMO

PURPOSE: To evaluate the effect of controlled medical conditions and risk of lifetime smoking history on the prevalence of branch retinal vein occlusion (BRVO) based on the Korea National Health and Nutrition Survey (KNHANES) database from 2017-2021. METHODS: The study population consisted of individuals aged ≥ 40 years who had completed ophthalmological questionnaires, underwent comprehensive ophthalmological examinations, and had at least one good-quality readable fundus photograph. Age, sex, hypertension status, diabetes status, dyslipidemia status, body mass index status, a history of chronic kidney disease (CKD), a lifetime smoking history of ≥ 100 cigarettes, and glaucoma were subjected to univariate and multivariate logistic regression analyses. RESULTS: The estimated prevalence (± standard error) of RVO was 0.5% (±0.1%). Significant risk factors were one-year increase in age, female sex, hypertension (stage 1, controlled, uncontrolled, and undiagnosed hypertension), underweight, pre-obesity, history of CKD, lifetime smoking history of ≥ 100 cigarettes, and glaucoma. Controlled diabetes decreased the risk of BRVO by 55% (odds ratio [OR] = 0.45, 95% confidence interval [CI] = 0.22-0.89, p = 0.022) and controlled hyper-high-density-lipoprotein (HDL)-cholesterolemia decreased the risk by 69% (OR = 0.31, 95% CI = 0.13-0.76, p = 0.010). CONCLUSION: This study, for the first time, reported the association between lifetime smoking history of ≥ 100 cigarettes and BRVO in Korea. The risk of BRVO was lower in participants with controlled diabetes and hypo-HDL-cholesterolemia.

3.
BMC Ophthalmol ; 24(1): 120, 2024 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-38491368

RESUMO

PURPOSE: To investigate the effect of topical nonsteroidal anti-inflammatory drugs (NSAIDs,) bromfenac on the intraretinal cystic lesions (IRC) when performing simultaneous cataract and idiopathic epiretinal membrane (iERM) surgery. METHODS: This study included patients with iERM who had been followed up for 6 months after vitrectomy, membrane removal, and concurrent cataract surgery. Eyes were treated with topical bromfenac or not. The baseline fluorescein angiography (FA) was obtained to assess the microvascular leakage (ML). Structural changes of macula, including IRC and central macular thickness (CMT) were assessed using optical coherence tomography (OCT). The main outcome measures were changes in IRCs and best-corrected visual acuity (BCVA) regarding FA findings. RESULTS: One hundred eighteen eyes were included. IRC and ML were observed in 51 eyes (43.2%) and 63 eyes (53.4%), respectively. The IRC did not show any association with the ML. Of total, 29 eyes (24.6%) were treated with topical bromfenac (Group A). Compared to Group B, topical bromfenac did not show beneficial effects in aspect of preventions for the newly developed IRC and treatment for pre-existed IRC. Whether the ML existed or not, topical bromfenac did not show any different effect on the changes in BCVA and IRC. CONCLUSION: When performing simultaneous cataract and ERM surgery, topical NSAIDs, bromfenac did not show beneficial effects on the preventions and treatment of IRC in both eyes with and without the ML.


Assuntos
Benzofenonas , Bromobenzenos , Catarata , Membrana Epirretiniana , Edema Macular , Humanos , Membrana Epirretiniana/cirurgia , Membrana Epirretiniana/patologia , Edema Macular/patologia , Tomografia de Coerência Óptica , Anti-Inflamatórios não Esteroides , Estudos Retrospectivos , Vitrectomia/métodos
4.
Ophthalmic Epidemiol ; 31(2): 112-118, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-37070930

RESUMO

PURPOSE: This study aimed to investigate the incidence and prevalence of, and treatment patterns for ocular complications in Korean patients with Marfan syndrome. METHODS: Incidence and prevalence of Marfan syndrome was calculated from 2010 to 2018, based on data from the Korean National Health Insurance Service (KNHIS). Diagnosis codes (for cataract, ectopia lentis, retinal detachment, etc.) and surgery reimbursement codes (lensectomy, phacoemulsification, buckling, vitrectomy, etc.) in the patients with Marfan syndrome were retrieved by complete enumeration of the data. RESULTS: The annual prevalence of Marfan syndrome adjusted by age and sex was gradually increased from 2.44 per 100,000 in 2010 to 4.36 per 100,000 in 2018. The age group of 10-19 years showed the highest prevalence. The prevalence of ectopia lentis was 21.7%, of whom 43.0% underwent surgeries. Surgery for RD was performed in 253 (14.1%) of 2044 patients during the study period. CONCLUSION: Although the most prevalent ophthalmologic manifestation was ectopia lentis, total prevalence rate of RD was more than 10% in the study period; thus, regular fundus examination is recommended for the patients with Marfan syndrome.


Assuntos
Ectopia do Cristalino , Síndrome de Marfan , Humanos , Criança , Adolescente , Adulto Jovem , Adulto , Síndrome de Marfan/complicações , Síndrome de Marfan/epidemiologia , Síndrome de Marfan/diagnóstico , Ectopia do Cristalino/epidemiologia , Ectopia do Cristalino/cirurgia , Ectopia do Cristalino/complicações , Acuidade Visual , Estudos Retrospectivos , República da Coreia/epidemiologia
5.
Nat Commun ; 14(1): 7921, 2023 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-38040714

RESUMO

Forming a hetero-interface is a materials-design strategy that can access an astronomically large phase space. However, the immense phase space necessitates a high-throughput approach for an optimal interface design. Here we introduce a high-throughput computational framework, InterMatch, for efficiently predicting charge transfer, strain, and superlattice structure of an interface by leveraging the databases of individual bulk materials. Specifically, the algorithm reads in the lattice vectors, density of states, and the stiffness tensors for each material in their isolated form from the Materials Project. From these bulk properties, InterMatch estimates the interfacial properties. We benchmark InterMatch predictions for the charge transfer against experimental measurements and supercell density-functional theory calculations. We then use InterMatch to predict promising interface candidates for doping transition metal dichalcogenide MoSe2. Finally, we explain experimental observation of factor of 10 variation in the supercell periodicity within a few microns in graphene/α-RuCl3 by exploring low energy superlattice structures as a function of twist angle using InterMatch. We anticipate our open-source InterMatch algorithm accelerating and guiding ever-growing interfacial design efforts. Moreover, the interface database resulting from the InterMatch searches presented in this paper can be readily accessed online.

6.
Phys Rev Lett ; 131(10): 106801, 2023 Sep 08.
Artigo em Inglês | MEDLINE | ID: mdl-37739384

RESUMO

Fractionalization without time-reversal symmetry breaking is a long-sought-after goal in the study of correlated phenomena. The earlier proposal of correlated insulating states at n±1/3 filling in twisted bilayer graphene and recent experimental observations of insulating states at those fillings strongly suggest that moiré graphene systems provide a new platform to realize time-reversal symmetric fractionalized states. However, the nature of fractional excitations and the effect of quantum fluctuation on the fractional correlated insulating states are unknown. We show that excitations of the fractional correlated insulator phases in the strong coupling limit carry fractional charges and exhibit fractonic restricted mobility. Upon introduction of quantum fluctuations, the resonance of "lemniscate" structured operators drives the system into quantum lemniscate liquid (QLL) or quantum lemniscate solid (QLS). We find an emergent U(1)×U(1) 1-form symmetry unifies distinct motions of the fractionally charged excitations in the strong coupling limit and in the QLL phase, while providing a new mechanism for fractional excitations in two dimensions. We predict emergent Luttinger liquid behavior upon dilute doping in the strong coupling limit due to restricted mobility and discuss implications at a general n±1/3 filling.

7.
Immune Netw ; 23(4): e32, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37670808

RESUMO

Most influenza vaccines currently in use target the highly variable hemagglutinin protein to induce neutralizing antibodies and therefore require yearly reformulation. T cell-based universal influenza vaccines focus on eliciting broadly cross-reactive T-cell responses, especially the tissue-resident memory T cell (TRM) population in the respiratory tract, providing superior protection to circulating memory T cells. This study demonstrated that intramuscular (i.m.) administration of the adenovirus-based vaccine expressing influenza virus nucleoprotein (rAd/NP) elicited weak CD8 TRM responses in the lungs and airways, and yielded poor protection against lethal influenza virus challenge. However, a novel "prime-and-deploy" strategy that combines i.m. vaccination of rAd/NP with subsequent intranasal administration of an empty adenovector induced strong NP-specific CD8+ TRM cells and provided complete protection against influenza virus challenge. Overall, our results demonstrate that this "prime-and-deploy" vaccination strategy is potentially applicable to the development of universal influenza vaccines.

8.
Korean J Ophthalmol ; 37(4): 299-306, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37400085

RESUMO

PURPOSE: We report the estimated incidence of, and risk factors for, recurrent anterior uveitis in patients with initial acute-onset Vogt-Koyanagi-Harada (VKH) disease using survival analyses. METHODS: Patients who were diagnosed with initial acute-onset VKH disease during 2003-2022 at two university hospitals were included. Recurrent anterior uveitis was defined as the first occurrence of the granulomatous anterior uveitis with anterior chamber cells and flare of 2+ or more by the Standardization of Uveitis Nomenclature (SUN) Working Group grading scheme, after the disappearance of conspicuous uveitis and serous retinal detachment for at least 3 months, regardless of systemic or local treatment. The univariate log-rank test and multivariate Cox regression analyses were performed, including patients' demographic characteristics, underlying diseases, presence of prodromal symptoms, duration of visual symptoms, visual acuity, slit-lamp and fundus findings, and height of serous retinal detachment. The treatment method and response to treatment were also included. RESULTS: The estimated incidence was 39.3% at 10 years. Fifteen of 55 patients (27.3%) had recurrent anterior uveitis during the mean follow-up of 4.5 years. The presence of focal posterior synechiae at the diagnosis increased the risk of recurrent anterior uveitis 6.97-fold compared to the absence of synechiae (95% confidence interval [CI], 2.20-22.11; p < 0.001). Use of systemic high-dose steroid therapy more than 7 days after the development of visual symptoms resulted in a hazard ratio of 4.55 (95% CI, 1.27-16.40; p = 0.020). CONCLUSIONS: This study reports the estimated incidence and risk factors of recurrent anterior uveitis in VKH disease from survival analyses. However, because of the retrospective nature of this study, it is hard to confirm the consistency of the medical records regarding risk factors, thus, the presence of focal posterior synechiae can be inconclusive as a risk factor. Further studies are warranted.


Assuntos
Descolamento Retiniano , Uveíte Anterior , Síndrome Uveomeningoencefálica , Humanos , Incidência , Descolamento Retiniano/diagnóstico , Descolamento Retiniano/epidemiologia , Descolamento Retiniano/etiologia , Estudos Retrospectivos , Fatores de Risco , Uveíte , Uveíte Anterior/diagnóstico , Uveíte Anterior/epidemiologia , Uveíte Anterior/tratamento farmacológico , Síndrome Uveomeningoencefálica/complicações , Síndrome Uveomeningoencefálica/diagnóstico , Síndrome Uveomeningoencefálica/tratamento farmacológico , Recidiva
9.
Nat Commun ; 14(1): 3716, 2023 06 22.
Artigo em Inglês | MEDLINE | ID: mdl-37349299

RESUMO

Accumulating evidence indicates that mitochondria play crucial roles in immunity. However, the role of the mitochondrial Krebs cycle in immunity remains largely unknown, in particular at the organism level. Here we show that mitochondrial aconitase, ACO-2, a Krebs cycle enzyme that catalyzes the conversion of citrate to isocitrate, inhibits immunity against pathogenic bacteria in C. elegans. We find that the genetic inhibition of aco-2 decreases the level of oxaloacetate. This increases the mitochondrial unfolded protein response, subsequently upregulating the transcription factor ATFS-1, which contributes to enhanced immunity against pathogenic bacteria. We show that the genetic inhibition of mammalian ACO2 increases immunity against pathogenic bacteria by modulating the mitochondrial unfolded protein response and oxaloacetate levels in cultured cells. Because mitochondrial aconitase is highly conserved across phyla, a therapeutic strategy targeting ACO2 may eventually help properly control immunity in humans.


Assuntos
Aconitato Hidratase , Caenorhabditis elegans , Humanos , Animais , Aconitato Hidratase/genética , Caenorhabditis elegans/genética , Caenorhabditis elegans/metabolismo , Ácido Oxaloacético , Oxaloacetatos , Resposta a Proteínas não Dobradas , Mamíferos/metabolismo
10.
PLoS One ; 18(5): e0285127, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37134078

RESUMO

INTRODUCTION: Little has been known about the intrableb structures associated with bleb function after trabeculectomy with amniotic membrane transplantation (AMT). The aim of this study is to analyze the characteristics of intrableb structures using anterior segment optical coherence tomography (AS-OCT) after trabeculectomy with AMT. METHODS: A total of 68 eyes of 68 patients with primary open-angle glaucoma who underwent trabeculectomy with AMT were included. Surgical success was defined as intraocular pressure (IOP) ≤ 18 mmHg and IOP reduction of ≥ 20% without medication on AS-OCT examination. Intrableb parameters, including bleb height, bleb wall thickness, striping layer thickness, bleb wall reflectivity, fluid-filled space score, fluid-filled space height, and microcyst formation were evaluated using AS-OCT. Logistic regression analysis was performed to determine factors associated with IOP control. RESULTS: Of the 68 eyes, 56 eyes were assigned to the success group and 12 eyes to the failure group. In the success group, bleb height (P = 0.009), bleb wall thickness (P = 0.001), striping layer thickness (P = 0.001), fluid-filled space score (P = 0.001), and frequency of microcyst formation (P = 0.001) were greater than those in the failure group. Bleb wall reflectivity was higher in the failure group than in the success group (P < 0.001). In the univariate logistic regression analysis, previous cataract surgery was significantly associated with surgical failure (odds ratio = 5.769, P = 0.032). CONCLUSION: A posteriorly extending fluid-filled space, tall bleb with low reflectivity, and thick striping layer were characteristics of successful filtering blebs after trabeculectomy with AMT.


Assuntos
Glaucoma de Ângulo Aberto , Glaucoma , Trabeculectomia , Humanos , Trabeculectomia/métodos , Glaucoma/diagnóstico por imagem , Glaucoma/cirurgia , Tomografia de Coerência Óptica/métodos , Segmento Anterior do Olho/diagnóstico por imagem , Glaucoma de Ângulo Aberto/diagnóstico por imagem , Glaucoma de Ângulo Aberto/cirurgia , Âmnio , Pressão Intraocular
11.
Nano Lett ; 23(8): 3137-3143, 2023 Apr 26.
Artigo em Inglês | MEDLINE | ID: mdl-37036942

RESUMO

Twisted van der Waals multilayers are widely regarded as a rich platform to access novel electronic phases thanks to the multiple degrees of freedom available for controlling their electronic and chemical properties. Here, we propose that the stacking domains that form naturally due to the relative twist between successive layers act as an additional "knob" for controlling the behavior of these systems and report the emergence and engineering of stacking domain-dependent surface chemistry in twisted few-layer graphene. Using mid-infrared near-field optical microscopy and atomic force microscopy, we observe a selective adhesion of metallic nanoparticles and liquid water at the domains with rhombohedral stacking configurations of minimally twisted double bi- and trilayer graphene. Furthermore, we demonstrate that the manipulation of nanoparticles located at certain stacking domains can locally reconfigure the moiré superlattice in their vicinity at the micrometer scale. Our findings establish a new approach to controlling moiré-assisted chemistry and nanoengineering.

12.
Am J Ophthalmol ; 252: 69-76, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-36963602

RESUMO

PURPOSE: We investigated the rate of ophthalmologic examinations to detect endogenous endophthalmitis in patients with pyogenic liver abscesses (PLAs) and the incidence and risk factors of endophthalmitis from a PLA caused by Klebsiella pneumoniae (PLA-K). DESIGN: Retrospective case series. METHODS: A total of 536 patients admitted to a university hospital in Korea to treat PLAs during 2012-2022 were included. The proportion of patients who were referred for ophthalmologic examinations was investigated and the incidence of endophthalmitis in 248 patients with PLA-K was calculated. Univariate and multivariate logistic regression analyses were performed to define risk factors including demographic characteristics, underlying diseases, radiologic findings, and systemic conditions. RESULTS: A comprehensive ophthalmologic examination was performed in 73.7% of all patients with PLAs, and the incidence of endophthalmitis from a PLA-K was 7.3%. A liver abscess >5 cm increased the incidence of endogenous endophthalmitis 4-fold compared with smaller abscesses (odds ratio [OR] = 4.01 [95% confidence interval {CI}, 1.02-15.78], P = .047) and portal or hepatic vein thrombophlebitis increased the incidence approximately 4-fold (OR = 4.04 [95% CI, 1.10-14.83], P = .036). Acute cholangitis was approximately 8-fold (OR = 8.33 [95% CI, 1.25-55.71], P = .029), and disseminated intravascular coagulation was approximately 6-fold (OR = 5.76 [95% CI, 1.22-27.21], P = .027) more related to prevalence of endophthalmitis. Other extrahepatic infections increased the incidence approximately 43-fold (OR = 43.06 [95% CI, 10.14-182.90], P < .001). CONCLUSIONS: Clinicians should consider the risk of endogenous endophthalmitis when PLA-K patients have large liver abscesses (>5 cm), acute cholangitis, portal or hepatic vein thrombophlebitis, disseminated intravascular coagulation, or other extrahepatic infections.


Assuntos
Coagulação Intravascular Disseminada , Endoftalmite , Infecções por Klebsiella , Abscesso Hepático Piogênico , Humanos , Klebsiella pneumoniae , Estudos Retrospectivos , Incidência , Coagulação Intravascular Disseminada/complicações , Infecções por Klebsiella/diagnóstico , Infecções por Klebsiella/epidemiologia , Infecções por Klebsiella/complicações , Abscesso Hepático Piogênico/diagnóstico , Abscesso Hepático Piogênico/epidemiologia , Abscesso Hepático Piogênico/complicações , Endoftalmite/diagnóstico , Endoftalmite/epidemiologia , Endoftalmite/etiologia , Fatores de Risco , Poliésteres
13.
RSC Adv ; 13(5): 2833-2840, 2023 Jan 18.
Artigo em Inglês | MEDLINE | ID: mdl-36756445

RESUMO

Environmental pollution, including the annual resurgence of particulate matter derived from road dust, is a serious issue worldwide. Typically, the size of road dust is less than 10 µm; thus, road dust can penetrate into human organs, including the brain, through inhalation and intake by mouth. Therefore, the toxicity of road dust has been intensively studied in vitro and in vivo. However, in vitro systems, including 2D cell cultures, cannot mimic complex human organs, and there are several discrepancies between in vivo and human systems. Here, we used human colon cells and organoids to evaluate the cytotoxicity of particulate matter derived from road dust. The toxicity of road dust collected in industrialized and high traffic areas and NIST urban particulate matter reference samples were evaluated in 2D and 3D human colon cells as well as colon organoids and their characteristics were carefully examined. Data suggest that the size and elemental compositions of road dust can correlate with colon organoid toxicity, and thus, a more careful assessment of the size and elemental compositions of road dust should be conducted to predict its effect on human health.

15.
Nat Commun ; 13(1): 7098, 2022 Nov 19.
Artigo em Inglês | MEDLINE | ID: mdl-36402757

RESUMO

Moiré superlattice systems such as transition metal dichalcogenide heterobilayers have garnered significant recent interest due to their promising utility as tunable solid state simulators. Recent experiments on a WSe2/WS2 heterobilayer detected incompressible charge ordered states that one can view as generalized Wigner crystals. The tunability of the transition metal dichalcogenide heterobilayer Moiré system presents an opportunity to study the rich set of possible phases upon melting these charge-ordered states. Here we use Monte Carlo simulations to study these intermediate phases in between incompressible charge-ordered states in the strong coupling limit. We find two distinct stripe solid states to be each preceded by distinct types of nematic states. In particular, we discover microscopic mechanisms that stabilize each of the nematic states, whose order parameter transforms as the two-dimensional E representation of the Moiré lattice point group. Our results provide a testable experimental prediction of where both types of nematic occur, and elucidate the microscopic mechanism driving their formation.

16.
Cancers (Basel) ; 14(12)2022 Jun 18.
Artigo em Inglês | MEDLINE | ID: mdl-35740678

RESUMO

The balance between cellular proliferation and apoptosis and the regulation of cell differentiation must be established to maintain tissue homeostasis. These cellular responses involve the kinase cascade-mediated Hippo pathway as a crucial regulator. Hence, Hippo pathway dysregulation is implicated in diverse diseases, including cancer. O-GlcNAcylation is a non-canonical glycosylation that affects multiple signaling pathways through its interplay with phosphorylation in the nucleus and cytoplasm. An abnormal increase in the O-GlcNAcylation levels in various cancer cells is a potent factor in Hippo pathway dysregulation. Intriguingly, Hippo pathway dysregulation also disrupts O-GlcNAc homeostasis, leading to a persistent elevation of O-GlcNAcylation levels, which is potentially pathogenic in several diseases. Therefore, O-GlcNAcylation is gaining attention as a protein modification that regulates the Hippo pathway. This review presents a framework on how O-GlcNAcylation regulates the Hippo pathway and forms a self-perpetuating cycle with it. The pathological significance of this self-perpetuating cycle and clinical strategies for targeting O-GlcNAcylation that causes Hippo pathway dysregulation are also discussed.

17.
Proc Natl Acad Sci U S A ; 119(24): e2109665119, 2022 Jun 14.
Artigo em Inglês | MEDLINE | ID: mdl-35679347

RESUMO

The information content of crystalline materials becomes astronomical when collective electronic behavior and their fluctuations are taken into account. In the past decade, improvements in source brightness and detector technology at modern X-ray facilities have allowed a dramatically increased fraction of this information to be captured. Now, the primary challenge is to understand and discover scientific principles from big datasets when a comprehensive analysis is beyond human reach. We report the development of an unsupervised machine learning approach, X-ray diffraction (XRD) temperature clustering (X-TEC), that can automatically extract charge density wave order parameters and detect intraunit cell ordering and its fluctuations from a series of high-volume X-ray diffraction measurements taken at multiple temperatures. We benchmark X-TEC with diffraction data on a quasi-skutterudite family of materials, (CaxSr[Formula: see text])3Rh4Sn13, where a quantum critical point is observed as a function of Ca concentration. We apply X-TEC to XRD data on the pyrochlore metal, Cd2Re2O7, to investigate its two much-debated structural phase transitions and uncover the Goldstone mode accompanying them. We demonstrate how unprecedented atomic-scale knowledge can be gained when human researchers connect the X-TEC results to physical principles. Specifically, we extract from the X-TEC-revealed selection rules that the Cd and Re displacements are approximately equal in amplitude but out of phase. This discovery reveals a previously unknown involvement of [Formula: see text] Re, supporting the idea of an electronic origin to the structural order. Our approach can radically transform XRD experiments by allowing in operando data analysis and enabling researchers to refine experiments by discovering interesting regions of phase space on the fly.

18.
Phys Rev Lett ; 128(15): 157602, 2022 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-35499883

RESUMO

Moiré systems provide a rich platform for studies of strong correlation physics. Recent experiments on heterobilayer transition metal dichalcogenide Moiré systems are exciting in that they manifest a relatively simple model system of an extended Hubbard model on a triangular lattice. Inspired by the prospect of the hetero-transition metal dichalcogenide Moiré system's potential as a solid-state-based quantum simulator, we explore the extended Hubbard model on the triangular lattice using the density matrix renormalization group. Specifically, we explore the two-dimensional phase space spanned by the key tuning parameters in the extended Hubbard model, namely, the kinetic energy strength and the further-range Coulomb interaction strengths. We find competition between Fermi fluid, chiral spin liquid, spin density wave, and charge order. In particular, our finding of the optimal further-range interaction for the chiral correlation presents a tantalizing possibility.

19.
Sci Adv ; 8(12): eabk1911, 2022 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-35333575

RESUMO

Moiré superlattices constructed from transition metal dichalcogenides have demonstrated a series of emergent phenomena, including moiré excitons, flat bands, and correlated insulating states. All of these phenomena depend crucially on the presence of strong moiré potentials, yet the properties of these moiré potentials, and the mechanisms by which they can be generated, remain largely open questions. Here, we use angle-resolved photoemission spectroscopy with submicron spatial resolution to investigate an aligned WS2/WSe2 moiré superlattice and graphene/WS2/WSe2 trilayer heterostructure. Our experiments reveal that the hybridization between moiré bands in WS2/WSe2 exhibits an unusually large momentum dependence, with the splitting between moiré bands at the Γ point more than an order of magnitude larger than that at K point. In addition, we discover that the same WS2/WSe2 superlattice can imprint an unexpectedly large moiré potential on a third, separate layer of graphene (g/WS2/WSe2), suggesting new avenues for engineering two-dimensional moiré superlattices.

20.
SSM Popul Health ; 17: 101061, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-35295744

RESUMO

Long-term and cumulative social experiences influence an individual's objective and subjective social status. Social determinants of health are more effectively investigated by longitudinal rather than cross-sectional studies. The primary focus of this study was the prospective effect of socioeconomic transition on health-related quality of life trajectories. The study population were adults over 18 years of age who responded in all nine waves of the Korea Health Panel (2009-2017). Data were analyzed by group-based trajectory modeling to identify health trajectories, and group-based multi-trajectory modeling to investigate combined change patterns of objective and subjective social status (i.e., multi-SES trajectories). To predict the effects of underlying socioeconomic measures on health trajectory group membership, we included these time-stable covariates in trajectory modeling and estimated the risk of belonging to each trajectory based on the measures. The health-related quality of life trajectories showed three patterns during the period 2013 to 2017; 13.7% of individuals had a low and declining health trajectory and the others had a higher stable health trajectory. Four types of multi-SES trajectory were derived during the period 2009 to 2013; the richer had a steeper income slope while there were slight changes in subjective social status among all groups. These combined longitudinal SES patterns in 2009-2013 were strong predictors of subsequent health trajectory group membership in 2013-2017. These findings indicate that rich countries, such as South Korea, may encounter growing income inequality, where individuals become entrenched in income disparity that pins down their perceptions of social position. Over time this rigid social structure will widen the gap in health-related quality of life.

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