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Strain engineering is a powerful tool with which to enhance semiconductor device performance1,2. Halide perovskites have shown great promise in device applications owing to their remarkable electronic and optoelectronic properties3-5. Although applying strain to halide perovskites has been frequently attempted, including using hydrostatic pressurization6-8, electrostriction9, annealing10-12, van der Waals force13, thermal expansion mismatch14, and heat-induced substrate phase transition15, the controllable and device-compatible strain engineering of halide perovskites by chemical epitaxy remains a challenge, owing to the absence of suitable lattice-mismatched epitaxial substrates. Here we report the strained epitaxial growth of halide perovskite single-crystal thin films on lattice-mismatched halide perovskite substrates. We investigated strain engineering of α-formamidinium lead iodide (α-FAPbI3) using both experimental techniques and theoretical calculations. By tailoring the substrate composition-and therefore its lattice parameter-a compressive strain as high as 2.4 per cent is applied to the epitaxial α-FAPbI3 thin film. We demonstrate that this strain effectively changes the crystal structure, reduces the bandgap and increases the hole mobility of α-FAPbI3. Strained epitaxy is also shown to have a substantial stabilization effect on the α-FAPbI3 phase owing to the synergistic effects of epitaxial stabilization and strain neutralization. As an example, strain engineering is applied to enhance the performance of an α-FAPbI3-based photodetector.
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OBJECTIVE: There are limited data evaluating the optimum blood pressure (BP) goal post mechanical thrombectomy (MT) and its effect on outcomes of patients with large vessel occlusions (LVO). The objective of this study was to compare the efficacy and safety of intensive versus conventional BP control after reperfusion with MT via a systematic review and meta-analysis of randomized controlled trials (RCTs). METHODS: We searched PubMed and Embase to obtain articles related to BP control post MT through September 2023. The primary outcome was functional independence (modified Rankin Scale [mRS] 0-2) at 3 months, while secondary outcomes included excellent outcome (mRS 0-1), symptomatic intracranial hemorrhage (sICH), and mortality. RESULTS: Four RCTs with 1,566 patients (762 randomized into intensive BP control vs. 806 randomized into conventional BP control) were included. Analysis showed that there was a lower likelihood of functional independence (mRS 0-2: odds ratio [OR]: 0.68, 95% confidence interval [CI] 0.51-0.91, p = 0.009) in the more intensive treatment group compared with the conventional treatment group. There was no statistically significant difference in achieving excellent outcome (mRS0-1: OR: 0.82, 95% CI: 0.63-1.07; p = 0.15), risk of sICH or mortality. INTERPRETATION: This systematic review and meta- analysis Indicates that in patients who achieved successful MT for acute ischemic stroke with LVO, intensive BP control was associated with a lower likelihood of functional independence at 3 months without significant difference in likelihood of achieving excellent outcome, sICH risk, or mortality. ANN NEUROL 2024;95:858-865.
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Pressão Sanguínea , Procedimentos Endovasculares , Ensaios Clínicos Controlados Aleatórios como Assunto , Humanos , Pressão Sanguínea/fisiologia , Procedimentos Endovasculares/métodos , AVC Isquêmico/terapia , AVC Isquêmico/cirurgia , Ensaios Clínicos Controlados Aleatórios como Assunto/métodos , Trombectomia/métodos , Resultado do TratamentoRESUMO
Spin-orbit torque (SOT)-driven deterministic control of the magnetic state of a ferromagnet with perpendicular magnetic anisotropy is key to next-generation spintronic applications including non-volatile, ultrafast and energy-efficient data-storage devices. However, field-free deterministic switching of perpendicular magnetization remains a challenge because it requires an out-of-plane antidamping torque, which is not allowed in conventional spin-source materials such as heavy metals and topological insulators due to the system's symmetry. The exploitation of low-crystal symmetries in emergent quantum materials offers a unique approach to achieve SOTs with unconventional forms. Here we report an experimental realization of field-free deterministic magnetic switching of a perpendicularly polarized van der Waals magnet employing an out-of-plane antidamping SOT generated in layered WTe2, a quantum material with a low-symmetry crystal structure. Our numerical simulations suggest that the out-of-plane antidamping torque in WTe2 is essential to explain the observed magnetization switching.
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Two-dimensional ferroic materials exhibit a variety of functional properties that can be tuned by temperature and pressure. CuInP2S6 is a layered material that is ferrielectric at room temperature and whose properties are a result of the unique structural arrangement of ordered Cu+ and In3+ cations within a (P2S6)4- anion backbone. Here, we investigate the effect of hydrostatic pressure on the structure of CuInP2S6 single crystals through a detailed Raman spectroscopy study. Analysis of the peak frequencies, intensities, and widths reveals four high pressure regimes. At 5 GPa, the material undergoes a monoclinic-trigonal phase transition. At higher pressures (5-12 GPa), we see Raman peak sharpening, indicative of a change in the electronic structure, followed by an incommensurate phase between 12 and 17 GPa. Above 17 GPa, we see evidence for bandgap reduction in material. The original state of the material is fully recovered upon decompression, showing that hydrostatic pressure could be used to tune the electronic and ferrielectric properties of CuInP2S6.
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Engineering magnetic anisotropy in a ferro- or ferrimagnetic (FM) thin film is crucial in a spintronic device. One way to modify the magnetic anisotropy is through the surface of the FM thin film. Here, we report the emergence of a perpendicular magnetic anisotropy (PMA) induced by interfacial interactions in a heterostructure comprised of a garnet ferrimagnet, Y3Fe5O12 (YIG), and a low-symmetry, high spin-orbit coupling (SOC) transition metal dichalcogenide, WTe2. At the same time, we also observed an enhancement in Gilbert damping in the WTe2-covered YIG area. Both the magnitude of interface-induced PMA and the Gilbert damping enhancement have no observable WTe2 thickness dependence down to a single quadruple layer, indicating that the interfacial interaction plays a critical role. The ability of WTe2 to enhance the PMA in FM thin film, combined with its previously reported capability to generate out-of-plane damping like spin torque, makes it desirable for magnetic memory applications.
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The nanomaterial landscape is so vast that a high-throughput combinatorial approach is required to understand structure-function relationships. To address this challenge, an approach for the synthesis and screening of megalibraries of unique nanoscale features (>10,000,000) with tailorable location, size, and composition has been developed. Polymer pen lithography, a parallel lithographic technique, is combined with an ink spray-coating method to create pen arrays, where each pen has a different but deliberately chosen quantity and composition of ink. With this technique, gradients of Au-Cu bimetallic nanoparticles have been synthesized and then screened for activity by in situ Raman spectroscopy with respect to single-walled carbon nanotube (SWNT) growth. Au3Cu, a composition not previously known to catalyze SWNT growth, has been identified as the most active composition.
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Catálise , Nanoestruturas/química , Bibliotecas de Moléculas Pequenas , Cobre/química , Ligas de Ouro/química , Ensaios de Triagem em Larga Escala , Nanopartículas Metálicas/química , Nanotubos de Carbono/química , Análise Espectral RamanRESUMO
OBJECTIVES: Alcohol misuse is known to be a risk factor for dementia. This study aimed to explore the association between risky drinking and cognitive impairment in a cohort study of middle aged and older people at risk of dementia. METHOD: The sample comprised 15,582 people aged 50 and over drawn from the PROTECT study. Risky drinking was defined according to a score of 4 or above on the Alcohol Use Disorders Identification Test (AUDIT). Cognitive function was assessed on visual episodic memory, spatial working memory, verbal working memory and verbal reasoning. RESULTS: Risky drinkers at baseline were more likely to be younger, male, white British, married, of higher educational status, current or past tobacco smokers and to have moderate to severe depression than non-risky drinkers. Risky drinkers were also more likely to be impaired on self-reported instrumental activities of daily living and subjective cognitive decline. At baseline, risky drinkers were less likely than non-risky drinkers to show impairment on verbal reasoning and spatial working memory but not on visual episodic memory or verbal working memory. Risky drinking at baseline predicted decline in cognitive function on visual episodic memory, verbal reasoning and spatial working memory at 2 year follow-up, but only verbal working memory and spatial working memory remained significant outcomes after controlling for possible confounders. CONCLUSION: Although of small effect size, the association between risky drinking and impairment on measures of working memory and visuospatial function warrants further examination; particularly given the possibility of partial reversibility in alcohol related cognitive impairment.
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Alcoolismo , Disfunção Cognitiva , Demência , Humanos , Masculino , Pessoa de Meia-Idade , Idoso , Estudos de Coortes , Atividades Cotidianas , Disfunção Cognitiva/epidemiologia , Disfunção Cognitiva/complicações , Memória de Curto Prazo , Consumo de Bebidas Alcoólicas/epidemiologiaRESUMO
Bio-inspired approaches represent potentially transformational methods to fabricate and activate non-natural materials for applications ranging from biomedical diagnostics to energy harvesting platforms. Recently, bio-based methods for the exfoliation of graphene in water have been developed, resulting in peptide-capped nanosheets; however, a clear understanding of the reaction system and peptide ligand structure remains unclear, limiting the advance of such approaches. Here the effects of reaction solution conditions and peptide ligand structure were systematically examined for graphene exfoliation, identifying key parameters to optimize material production. For this, the P1 peptide, identified with affinity for graphene, was exploited to drive exfoliation of bulk graphite to generate the final materials. The peptide was modified at both the N- and C-terminus with a 10-carbon chain fatty acid to explore the effects of a hydrophobic domain on the exfoliation process. The system was examined as a function of sonication time, pH, reagent concentration, and graphite source, where the final materials were fully characterized using a suite of approaches. Collectively, these results demonstrated that maximum graphene production was achieved using the parent P1 peptide after 12 h of sonication under basic conditions. While the exfoliation efficiency was slightly lower for the fatty acid modified peptides, the graphene produced using these biomolecules had fewer defects incorporated, potentially from the wrapping of the nanosheet edge by the aliphatic domain. Such results are important to provide key reaction designs to optimize the reproducibility of graphene exfoliation using biomimetic approaches.
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A challenge in the synthesis of single-wall carbon nanotubes (SWCNTs) is the lack of control over the formation and evolution of catalyst nanoparticles and the lack of control over their size or chirality. Here, zeolite MFI nanosheets (MFI-Ns) are used to keep cobalt (Co) nanoparticles stable during prolonged annealing conditions. Environmental transmission electron microscopy (ETEM) shows that the MFI-Ns can influence the size and shape of nanoparticles via particle/support registry, which leads to the preferential docking of nanoparticles to four or fewer pores and to the regulation of the SWCNT synthesis products. The resulting SWCNT population exhibits a narrow diameter distribution and SWCNTs of nearly all chiral angles, including sub-nm zigzag (ZZ) and near-ZZ tubes. Theoretical simulations reveal that the growth of these unfavorable tubes from unsupported catalysts leads to the rapid encapsulation of catalyst nanoparticles bearing them; their presence in the growth products suggests that the MFI-Ns prevent nanoparticle encapsulation and prologue ZZ and near-ZZ SWCNT growth. These results thus present a path forward for controlling nanoparticle formation and evolution, for achieving size- and shape-selectivity at high temperature, and for controlling SWCNT synthesis.
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BACKGROUND: Patients with large-vessel occlusion (LVO) who initially present to a non-thrombectomy-capable center ("spoke") have worse outcomes than those presenting directly to a thrombectomy-capable center ("hub"). Furthermore, patients who suffer in-hospital strokes (IHS) suffer worse outcomes than those suffering strokes in the community. Data on patients who suffer IHS at a spoke hospital is lacking. We aim to characterize this particularly vulnerable population, define their outcomes, and compare them to patients who develop IHS at a hub institution. METHODS: We retrospectively reviewed prospectively collected data from patients suffering an IHS at a spoke hospital who were then transferred to the hub hospital for endovascular therapy (EVT). We then compared outcomes of these patients under EVT after developing IHS at the hub institution. RESULTS: A total of 108 IHS patients met inclusion criteria: 91 (84%) at a spoke facility and 17 (16%) at the hub facility. Baseline characteristics and reason for hospital admission were comparable between the two groups. Time from imaging to IV-tPA administration (17 vs. 70 min, p = 0.01) and time to EVT (120 vs. 247 min, p = 0.001) were significantly shorter in the hub group. More patients had a 90 day-mRS of 0-3 in the hub group than the spoke group (57% vs 22%, p < 0.05). CONCLUSION: Patients undergoing EVT after suffering IHS at a spoke hospital have significantly higher rates of poor outcomes compared to patients who suffer IHS at a hub hospital. Prolonged time delays in the initiation of IV-tPA and EVT represent areas of improvement.
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Procedimentos Endovasculares , Fibrinolíticos/administração & dosagem , Pacientes Internados , Transferência de Pacientes , Acidente Vascular Cerebral/terapia , Trombectomia , Terapia Trombolítica , Tempo para o Tratamento , Ativador de Plasminogênio Tecidual/administração & dosagem , Administração Intravenosa , Idoso , Idoso de 80 Anos ou mais , Procedimentos Endovasculares/efeitos adversos , Procedimentos Endovasculares/mortalidade , Feminino , Fibrinolíticos/efeitos adversos , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Fatores de Risco , Acidente Vascular Cerebral/diagnóstico , Acidente Vascular Cerebral/mortalidade , Acidente Vascular Cerebral/fisiopatologia , Trombectomia/efeitos adversos , Trombectomia/mortalidade , Terapia Trombolítica/efeitos adversos , Terapia Trombolítica/mortalidade , Fatores de Tempo , Ativador de Plasminogênio Tecidual/efeitos adversos , Resultado do TratamentoRESUMO
Alcohol-related dementia represents an underrecognised mental disorder with both clinical and public mental health aspects. There is considerable scope for improving its assessment within both mainstream and specialist mental health services, but ongoing challenges remain in ensuring its timely detection so that appropriate preventative and rehabilitative interventions can be applied. Declaration of interest None.
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Transtornos Relacionados ao Uso de Álcool , Demência , Transtornos Relacionados ao Uso de Álcool/diagnóstico , Transtornos Relacionados ao Uso de Álcool/epidemiologia , Transtornos Relacionados ao Uso de Álcool/fisiopatologia , Síndrome Alcóolica de Korsakoff/diagnóstico , Síndrome Alcóolica de Korsakoff/epidemiologia , Síndrome Alcóolica de Korsakoff/fisiopatologia , Demência/induzido quimicamente , Demência/diagnóstico , Demência/epidemiologia , Demência/fisiopatologia , HumanosRESUMO
BACKGROUND: Two-stage breast reconstruction with tissue expanders is one of the most common plastic surgery procedures. Acellular dermal matrix (ADM) has become popular for its ability to improve expansion parameters and aesthetics, albeit with a higher complication profile. We present data that support redefining 2-stage reconstruction to include tissue expanders regardless of final reconstructive modality to act as a bridge. Furthermore, we show that cooperation with the ablative surgeon and technical refinements support ADM omission from the first stage of reconstruction. METHODS: We retrospectively reviewed charts from the senior author's (D.A.J.) private practice over a 10-year follow-up period. Inclusion criteria included all women over 18 years who underwent mastectomy and had a tissue expander placed immediately or in a delayed fashion and successfully completed tissue expansion and are finished with the second stage of reconstruction or awaiting second stage of reconstruction. Demographic data, tissue expander filling data, final reconstruction, aesthetic outcome, and complications were tabulated. RESULTS: A total of 118 women (165 breasts) met inclusion criteria. There were no statistically significant differences in initial fill volume (P = 0.094), number of visits until final expansion (P = 0.677), or final fill volume (P = 0.985) between the ADM and non-ADM cohorts. In addition, non-ADM patients had superior aesthetic scores with respect to defects other than scarring (P = 0.015), projection (P = 0.013), and inframammary fold quality (P = 0.009). Fifteen percent of women decided to change desired final reconstruction modality during the tissue expansion phase. CONCLUSIONS: This reconstructive algorithm emphasizes surgical cooperation between the ablative and reconstructive surgeon, improved technique, and patient education. This focus translates into maintained tissue expansion, aesthetically pleasing results, and allows for the omission of ADM from reconstruction.
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Mamoplastia/métodos , Expansão de Tecido/métodos , Derme Acelular , Adulto , Feminino , Seguimentos , Humanos , Mamoplastia/instrumentação , Mastectomia , Pessoa de Meia-Idade , Avaliação de Resultados em Cuidados de Saúde , Estudos Retrospectivos , Expansão de Tecido/instrumentação , Dispositivos para Expansão de TecidosAssuntos
Infecções por Coronavirus/complicações , Síndrome de Guillain-Barré/fisiopatologia , Síndrome de Secreção Inadequada de HAD/fisiopatologia , Condução Nervosa , Pneumonia Viral/complicações , Disautonomias Primárias/fisiopatologia , Idoso , Betacoronavirus , COVID-19 , Diarreia/etiologia , Eletromiografia , Infecções por Bactérias Gram-Negativas/diagnóstico , Infecções por Bactérias Gram-Negativas/etiologia , Síndrome de Guillain-Barré/diagnóstico , Síndrome de Guillain-Barré/etiologia , Síndrome de Guillain-Barré/terapia , Humanos , Hipertensão/etiologia , Hipertensão/fisiopatologia , Hipotensão/etiologia , Hipotensão/fisiopatologia , Imunoglobulinas Intravenosas/uso terapêutico , Fatores Imunológicos/uso terapêutico , Síndrome de Secreção Inadequada de HAD/etiologia , Masculino , Pandemias , Pneumonia Associada à Ventilação Mecânica/diagnóstico , Pneumonia Associada à Ventilação Mecânica/etiologia , Disautonomias Primárias/diagnóstico , Disautonomias Primárias/etiologia , Disautonomias Primárias/terapia , Quadriplegia/etiologia , Quadriplegia/fisiopatologia , SARS-CoV-2 , Stenotrophomonas maltophilia , Taquicardia/etiologia , Taquicardia/fisiopatologiaAssuntos
Alcoolismo/tratamento farmacológico , Hemorragias Intracranianas/tratamento farmacológico , Deficiência de Tiamina/tratamento farmacológico , Tiamina/administração & dosagem , Complexo Vitamínico B/administração & dosagem , Alcoolismo/epidemiologia , Alcoolismo/metabolismo , Humanos , Hemorragias Intracranianas/epidemiologia , Hemorragias Intracranianas/metabolismo , Tiamina/metabolismo , Deficiência de Tiamina/epidemiologia , Deficiência de Tiamina/metabolismo , Complexo Vitamínico B/metabolismoRESUMO
Percutaneous transluminal mitral commissurotomy (PTMC) has become the standard of care for severe mitral stenosis with favorable anatomy. Although the complications have reduced over the years, the need for emergency surgical rescue persists. This study evaluates the outcomes of surgical rescue performed within 24 h of undergoing PTMC from 1 January 2013 to 31 December 2019. Out of 2259 PTMC patients, 22 patients (< 1%) required rescue mitral valve surgery. Out of 22 patients, 17 patients (77.27%) developed mitral regurgitation; five patients (22.7%) had cardiac tamponade. Mitral valve replacement was performed in 20 patients (90.9%), while two patients (9.1%) underwent mitral valve repair. Cardiac tamponade was secondary to injury of the left atrium (9.1%), left ventricle (4.5%), and right ventricle (9.1%). Concomitant tricuspid valve repair was done in three patients (13.6%). Intraoperatively, anterior mitral leaflet tear was seen in 68.2% while posterior mitral leaflet tear was noted in 9.1%. Postoperatively, three patients (13.6%) required prolonged ventilation, incidence of stroke was 4.5% (n = 1), and in-hospital mortality was 4.5% (n = 1). Intra-aortic balloon pump was used in three patients (13.6%), preoperatively. We conclude that post-PTMC complications are rare, but they require urgent surgical intervention.
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Schizencephaly is a rare congenital anomaly characterized by the formation of abnormal clefts in the brain. Despite the association of psychotic symptoms with various brain abnormalities or insults, their occurrence in individuals with schizencephaly is relatively infrequent. The association of bipolar disorder, with or without psychosis, with schizencephaly is rarer. A systematic search on PubMed using "Schizencephaly AND Bipolar Disorder" yielded only four case studies specifically addressing the connection between these two conditions. Here, we present a case of a 22-year-old male patient with a history of childhood seizures who developed first episode psychosis along with manic symptoms and was found to have closed-lip schizencephaly.
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We present a case report of a previously healthy 29 year old woman who developed thromboembolic events in rapid fashion after a recent orthopedic surgery. This case highlights the importance of understanding risk factors for clot formation even in those who had no prior events, the efficacy of novel aspiration techniques to remove emboli, and how rapid triaging of acute symptoms can lead to the best outcomes. She presented to the emergency department with shortness of breath and was found to have a large bilateral pulmonary embolus. She was given intravenous thrombolysis. Shortly after, she developed aphasia and right-sided weakness and was taken emergently for mechanical thrombectomy of a left middle cerebral artery occlusion. She was later found to have a patent foramen ovale and a highly mobile right atrial thrombus which was aspirated. Further evaluation revealed right lower extremity peroneal and popliteal deep venous thrombi. She was placed on anticoagulation, made a full clinical recovery, and was discharged home. Prompt recognition of symptoms, efficient in-hospital work flow, and a multidisciplinary approach led to an outstanding outcome in this young patient.
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Context: An unfavorable event that can hinder endodontic treatment and affect the outcome of root canal treatment is the separation of endodontic instruments. Endodontic instrument separation can occur due to clinical or metallurgical factors. Friction between the ultrasonic tip and the remaining dentin generates heat, which is subsequently transferred to the external root surface. Elevated temperatures exceeding 10°C above body temperature for more than a minute may result in injury to periodontal or bone tissue. Aim: The aim of this study was to evaluate and compare temperature rise on the external root surface of teeth during retrieval of broken NiTi instrument using two different ultrasonic tips and two power settings. Materials and Methods: In each group, a sample size of 8 was sufficient to attain a statistical power exceeding 90%, enabling the detection of a minimum mean difference of 0.9204 (delta) through a one-way ANOVA test at a 95% confidence level (alpha 0.05). After access opening and working length determination, samples were randomly distributed into two groups - Group 1 (A and B) - ProUltra tip at high and low power settings and Group 2 (A and B) - Cric Dental IR3 at high and low power settings. The temperature rise was measured using K-type thermocouple thermometer. The comparisons were analyzed using the Kruskal-Wallis test with pairwise comparisons using the Dunn's test. Results: Group 1A and Group 1B resulted in lower heat generation compared to Group 2A and 2B and its difference was statistically significant (P < 0.05). Minimum temperature rise is seen in the ProUltra group at lower power settings (Group 1A) at the apical level and maximum temperature rise is seen in the Cric Dental IR3 group at higher power settings (Group 2B) at the middle third level. Conclusion: It was found that there is a significant temperature rise seen when ultrasonic tips are used for the retrieval of separated files, especially at higher power settings. The ProUltra tip demonstrated the lowest temperature rise at lower power settings, particularly at the apical level, whereas the IR3 Cric Dental tip exhibited the highest temperature rise, notably at higher power settings and the middle third level.