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1.
Nat Commun ; 15(1): 5709, 2024 Jul 08.
Artículo en Inglés | MEDLINE | ID: mdl-38977696

RESUMEN

Stability has been a long-standing concern for solution-processed perovskite photovoltaics and their practical applications. However, stable perovskite materials for photovoltaic remain insufficient to date. Here we demonstrate a series of ultrastable Dion-Jacobson (DJ) perovskites (1,4-cyclohexanedimethanammonium)(methylammonium)n-1PbnI3n+1 (n ≥ 1) for photovoltaic applications. The scalable technology by blade-coated solar cells for the designed DJ perovskites (nominal n = 5) achieves a maximum stabilized power conversion efficiency (PCE) of 19.11% under an environmental atmosphere. Un-encapsulated cells by blade-coated technology retain 92% of their initial efficiencies for over 4000 hours under ~90% relative humidity (RH) aging conditions. More importantly, these cells also exhibit remarkable thermal (85 °C) and operational stability, which shows negligible efficiency loss after exceeding 5000-hour heat treatment or after operation at maximum power point (MPP) exceeding 6000 hours at 45 °C under a 100 mW cm-2 continuous light illumination.

2.
Phys Med Biol ; 2024 Jul 15.
Artículo en Inglés | MEDLINE | ID: mdl-39008990

RESUMEN

OBJECTIVE: This study aimed to employ a two-stage deep learning method to accurately detect small aneurysms (4-10 mm in size) in computed tomography angiography (CTA) images. Methods: This study included 956 patients from 6 hospitals and a public dataset obtained with 6 CT scanners from different manufacturers. The proposed method consists of two components: a lightweight and fast head region selection (HRS) algorithm and an adaptive 3D nnU-Net network, which is used as the main architecture for segmenting aneurysms. Segments generated by the deep neural network were compared with expert-generated manual segmentation results and assessed using Dice scores. Results: The area under the curve (AUC) exceeded 79% across all datasets. In particular, the precision and AUC reached 85.2% and 87.6%, respectively, on certain datasets. The experimental results demonstrated the promising performance of this approach, which reduced the inference time by more than 50% compared to direct inference without HRS. Conclusion: Compared with a model without HRS, the deep learning approach we developed can accurately segment aneurysms by automatically localizing brain regions and can accelerate aneurysm inference by more than 50%. Keywords: Deep Learning, CT Angiography, Aneurisms.

3.
Mil Med Res ; 11(1): 46, 2024 Jul 11.
Artículo en Inglés | MEDLINE | ID: mdl-38992778

RESUMEN

BACKGROUND: Subarachnoid hemorrhage (SAH) is a subtype of hemorrhagic stroke characterized by high mortality and low rates of full recovery. This study aimed to investigate the epidemiological characteristics of SAH between 1990 and 2021. METHODS: Data on SAH incidence, mortality, and disability-adjusted life-years (DALYs) from 1990 to 2021 were obtained from the Global Burden of Disease Study (GBD) 2021. Estimated annual percentage changes (EAPCs) were calculated to evaluate changes in the age-standardized rate (ASR) of incidence and mortality, as well as trends in SAH burden. The relationship between disease burden and sociodemographic index (SDI) was also analyzed. RESULTS: In 2021, the incidence of SAH was found to be 37.09% higher than that in 1990; however, the age-standardized incidence rates (ASIRs) showed a decreased [EAPC: -1.52; 95% uncertainty interval (UI) -1.66 to -1.37]. Furthermore, both the number and rates of deaths and DALYs decreased over time. It was observed that females had lower rates compared to males. Among all regions, the high-income Asia Pacific region exhibited the highest ASIR (14.09/100,000; 95% UI 12.30/100,000 - 16.39/100,000) in 2021, with an EPAC for ASIR < 0 indicating decreasing trend over time for SAH ASIR. Oceania recorded the highest age-standardized mortality rates (ASMRs) and age-standardized DALYs rates among all regions in 2021 at values of respectively 8.61 (95% UI 6.03 - 11.95) and 285.62 (95% UI 209.42 - 379.65). The burden associated with SAH primarily affected individuals aged between 50 - 69 years old. Metabolic risks particularly elevated systolic blood pressure were identified as the main risk factors contributing towards increased disease burden associated with SAH when compared against environmental or occupational behavioral risks evaluated within the GBD framework. CONCLUSIONS: The burden of SAH varies by gender, age group, and geographical region. Although the ASRs have shown a decline over time, the burden of SAH remains significant, especially in regions with middle and low-middle SDI levels. High systolic blood pressure stands out as a key risk factor for SAH. More specific supportive measures are necessary to alleviate the global burden of SAH.


Asunto(s)
Carga Global de Enfermedades , Hemorragia Subaracnoidea , Humanos , Hemorragia Subaracnoidea/epidemiología , Masculino , Femenino , Incidencia , Persona de Mediana Edad , Anciano , Adulto , Carga Global de Enfermedades/tendencias , Años de Vida Ajustados por Discapacidad/tendencias , Salud Global/estadística & datos numéricos , Anciano de 80 o más Años
4.
J Phys Chem B ; 2024 Jul 15.
Artículo en Inglés | MEDLINE | ID: mdl-39007639

RESUMEN

Singlet fission (SF) is a triplet generation mechanism capable of turning a singlet exciton into two triplet excitons. It has the potential to enhance the power conversion efficiency of single-junction solar cells. Perylene diimides (PDIs) are a class of dye molecules with photovoltaic properties and are beginning to receive more and more attention due to their potential for SF. Here, we report a selenium-substituted PDI dimer, Se-PDI-II, and we studied its SF mechanism by using steady-state, transient absorption, and time-resolved photoluminescence spectroscopy. Compared with the unsubstituted dimer PDI-II, we found that the introduction of selenium atoms can suppress excimer emission during the SF process, showing much higher SF efficiency and triplet yield.

5.
Artículo en Inglés | MEDLINE | ID: mdl-38923848

RESUMEN

BACKGROUND: Frailty is a common geriatric syndrome associated with reduced reserves and increased vulnerability to stressors among older adults. Vitamin D deficiency has been implicated in frailty, as it is essential for maintaining musculoskeletal functions. The relationship between dynamic changes in vitamin D levels and frailty over time has not been extensively studied. METHODS: This study utilized data from the UK Biobank. Baseline and longitudinal changes in vitamin D levels were measured. Frailty status was assessed using both the frailty phenotype and frailty index approaches and classified as robust, pre-frail, or frail. Changes in frailty status were assessed by frailty phenotype at baseline (2006-2010) and the follow-up (2012-2013). Mixed effect model was performed to examine the association between vitamin D levels and frailty status. Using multistate transition models, we assessed the impact of increasing vitamin D levels on the probabilities of transitioning between robust, pre-frail, and frail states. RESULTS: Based on the frailty phenotype, 287 926 individuals (64.8%) were identified as having various degrees of frailty (median age 58.00 [51.00, 64.00] years, 55.9% females). Using the frailty index approach, 250 566 individuals (56%) were found to have different levels of frailty (median age 59.00 [51.00, 64.00] years, 55.3% females). Baseline vitamin D levels were found to be significantly associated with frailty status (frailty phenotype: ORfrail 0.78, 95% CI [0.76, 0.79], P < 0.001; frailty index: ORfrail 0.80, 95% CI [0.78, 0.81], P < 0.001). Dynamic changes in vitamin D levels were also found to be associated with changes in frailty over time. Furthermore, increasing vitamin D levels were associated with a transition from frailty to a healthier status. A higher degree of vitamin D (estimated at 1 nmol/L) was associated with a lower risk of transitioning from robust to prefrail (HR 0.997, 95% CI [0.995, 0.999]) and from prefrail to frail (HR 0.992, 95% CI [0.988, 0.995]). CONCLUSIONS: This study highlights the importance of vitamin D in the context of frailty. Low vitamin D levels are associated with increased frailty risk, while increasing vitamin D levels may contribute to improving frailty status. Recognizing the relationship between vitamin D levels and frailty can inform personalized management and early interventions for frail individuals. Further research is needed to explore the potential effects of vitamin D interventions on frailty and deepen our understanding of the biological connections between vitamin D and frailty.

6.
Eur J Neurol ; : e16380, 2024 Jun 24.
Artículo en Inglés | MEDLINE | ID: mdl-38924331

RESUMEN

BACKGROUND AND PURPOSE: This study aimed to investigate the effect of collateral circulation on the outcomes of thrombectomy versus medical management alone in basilar artery occlusion (BAO) patients with varying stroke severities. METHODS: Data from the ATTENTION cohort were used to perform a post-hoc analysis comparing the outcomes of thrombectomy with medical management in BAO patients with varying degrees of collateral circulation and stroke severity. Basilar Artery on Computed Tomography Angiography (BATMAN) scores were used to quantify the collateral circulation, and the effect was estimated through a primary outcome of 90-day functional independence (modified Rankin Scale score, mRS ≤2). Favorable versus unfavorable BATMAN scores were analyzed as both continuous and categorical variables, and an adjusted multivariate regression model was applied. RESULTS: Among 221 BAO patients, thrombectomy significantly improved functional independence compared to medical management in patients with favorable BATMAN scores (aOR 7.75, 95% CI 2.78-26.1), but not in those with unfavorable BATMAN scores (aOR 1.33, 95% CI 0.28-6.92; pinteraction = 0.028). When treated as a continuous variable, increased BATMAN score was found to be associated with a higher likelihood of functional independence in the thrombectomy group (aOR 1.97, 95% CI 1.44-2.81; pinteraction = 0.053). In severe stroke patients with higher BATMAN scores (National Institutes of Health Stroke Scale (NIHSS) ≥21), we identified a significant interaction for treatment effect with thrombectomy compared to medical management (pinteraction = 0.042). CONCLUSION: An increased BATMAN score was significantly associated with a higher probability of functional independence after thrombectomy than after medical management, particularly in patients with severe BAO.

7.
Sheng Li Xue Bao ; 76(3): 438-446, 2024 Jun 25.
Artículo en Chino | MEDLINE | ID: mdl-38939938

RESUMEN

Oocyte maturation and early embryonic development are key steps in the reproductive physiology of female mammals, and any error in this process can adversely affect reproductive development. Recent studies have shown that epigenetic modifications of histones play important roles in the regulation of oocyte meiosis and quality assurance of early embryonic development. Histone deacetylase 11 (HDAC11) is the smallest known member of the histone deacetylases (HDACs) family, and inhibition of HDAC11 activity significantly suppresses the rate of oocyte maturation, as well as the development of 8-cell and blastocyst embryos at the embryonic stage. This paper focuses on recent progress on the important role of HDAC11 in the regulation of mammalian oocyte maturation and early embryonic development, hoping to gain insights into the key roles played by epitope-modifying proteins represented by HDAC11 in the regulation of mammalian reproduction and their molecular mechanisms.


Asunto(s)
Desarrollo Embrionario , Histona Desacetilasas , Oocitos , Animales , Oocitos/fisiología , Desarrollo Embrionario/fisiología , Histona Desacetilasas/metabolismo , Histona Desacetilasas/fisiología , Histona Desacetilasas/genética , Femenino , Humanos , Oogénesis/fisiología , Mamíferos/embriología , Meiosis/fisiología
8.
Pediatr Neurol ; 155: 193-199, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38692081

RESUMEN

BACKGROUND: Current studies on the impact of sex in the prognosis of childhood arterial ischemic stroke (AIS) are limited. We aimed to explore the sex differences in outcomes in patients with childhood AIS. METHODS: A retrospective analysis was conducted using the prospective data from the Chinese Pediatric Ischemic Stroke Registry. Baseline characteristics between sexes were compared in the total population cohort, propensity score (PS)-matched cohort, and inverse probability of treatment weighting cohort. Multivariate logistic regression and ordinal regression were used to analyze the association of sex with outcomes. Mixed-effects regression model was applied to further analyze the improvement in pediatric modified Rankin Scale (mRS) scores between sexes from 90 days to one year. Survival analysis was used to estimate the recurrence rates during the follow-up period. RESULTS: A total of 468 patients were finally included. Multivariate logistic regression showed that there were no significant differences between females and males in achieving favorable outcome (odds ratio [OR] 1.04, 95% confidence interval [CI] 0.63 to 1.72), functional independence (OR 0.98, 95% CI 0.59 to 1.63), or shift to worse pediatric mRS scores (OR 0.83, 95% CI 0.59 to 1.17) at 90-day. Mixed-effects regression and survival analysis indicated that females and males exhibited comparable functional recovery from 90 days to one year and had similar recurrent risk during the follow-up period. CONCLUSIONS: This nationally-representative observational study indicated that both male and female pediatric patients with AIS exhibited comparable similar clinical outcomes at 90 days, as well as similar improvements and risks of recurrence during the follow-up period.


Asunto(s)
Accidente Cerebrovascular Isquémico , Sistema de Registros , Humanos , Femenino , Masculino , Niño , Pronóstico , Preescolar , Accidente Cerebrovascular Isquémico/epidemiología , China/epidemiología , Estudios Retrospectivos , Caracteres Sexuales , Adolescente , Lactante , Factores Sexuales , Pueblos del Este de Asia
9.
Nano Lett ; 24(22): 6568-6575, 2024 Jun 05.
Artículo en Inglés | MEDLINE | ID: mdl-38787693

RESUMEN

Zero-dimensional metal halides have received wide attention due to their structural diversity, strong quantum confinement, and associated excellent photoluminescence properties. A reversible and tunable luminescence would be desirable for applications such as anti-counterfeiting, information encryption, and artificial intelligence. Yet, these materials are underexplored, with little known about their luminescence tuning mechanisms. Here we report a pyramidal coplanar dimer, (TBA)Sb2Cl7 (TBA = tetrabutylammonium), showing broadband emission wavelength tuning (585-650 nm) by simple thermal treatment. We attribute the broad color change to structural disorder induced by varying the heat treatment temperatures. Increasing the heating temperature transitions the material from long-range ordered crystalline phase to highly disordered glassy phase. The latter exhibits stronger electron-phonon coupling, enhancing the self-trapped exciton emission efficiency. The work provides a new material platform for manifold optical anti-counterfeiting applications and sheds light on the emission color tuning mechanisms for further design of stimuli-responsive materials.

10.
Nano Lett ; 2024 May 16.
Artículo en Inglés | MEDLINE | ID: mdl-38753313

RESUMEN

Carrier multiplication (CM) in semiconductors, the process of absorbing a single high-energy photon to form two or more electron-hole pairs, offers great potential for the high-response detection of high-energy photons in the ultraviolet spectrum. However, compared to two-dimensional semiconductors, conventional bulk semiconductors not only face integration and flexibility bottlenecks but also exhibit inferior CM performance. To attain efficient CM for ultraviolet detection, we designed a two-terminal photodetector featuring a unilateral Schottky junction based on a two-dimensional γ-InSe/graphene heterostructure. Benefiting from a strong built-in electric field, the photogenerated high-energy electrons in γ-InSe, an ideal ultraviolet light-absorbing layer, can efficiently transfer to graphene without cooling. It results in efficient CM within the graphene, yielding an ultrahigh responsivity of 468 mA/W and a record-high external quantum efficiency of 161.2% when it is exposed to 360 nm light at zero bias. This work provides valuable insights into developing next-generation ultraviolet photodetectors with high performance and low-power consumption.

11.
Neurol Sci ; 45(7): 3495-3501, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38714597

RESUMEN

BACKGROUND: Shunt obstruction is a type of ventriculoperitoneal shunt (VPS) failure. Whether changes in cerebrospinal fluid (CSF) parameters can influence shunt outcomes or not is debatable. METHODS: In this study, we retrospectively included adult hydrocephalus patients who received VPS from 6 general hospitals in different provinces of China from November 2013 to September 2021. The inclusion criteria: Patients with hydrocephalus of all etiologies underwent shunt surgery from 6 general hospitals in different provinces of China were included in the study. The exclusion criteria: 1.Patients under the age of 18; 2.Patients who had previous shunt surgery; 3. Shunt failure from other factors; 4.Patients died from other causes; 5. Patients with incomplete data. The CSF of shunt patients had been analyzed at the time of shunt insertion. The CSF samples were collected and analyzed when the shunt was implanted. The relationship between CSF parameters and the incidence rate of shunt obstruction in one year was analyzed. RESULTS: A total of 717 eligible patients from 6 hospitals were included, of whom 59(8.23%) experienced obstruction. Multivariate logistic regression analysis identified that protein level(odds ratio [OR] 1.161, 95% CI 1.005 ~ 1.341, p = 0.043), decreased glucose level(< 2.5 mmol/L)(odds ratio 3.784, 95% confidence interval 1.872 ~ 7.652, p = 0.001) and protein level increase(> 0.45 g/L) (odds ratio 3.653, 95% confidence interval 1.931 ~ 6.910, p = 0.001)were independent risk factors of shunt obstruction. CONCLUSION: This study suggested that increased protein level (> 0.45 g/L) and decreased glucose level (< 2.5 mmol/L) in CSF indicated an increased risk of shunt obstruction in a patient with hydrocephalus. Thus, shunt surgery should be more carefully considered when the CSF glucose and protein were abnormal.


Asunto(s)
Hidrocefalia , Derivación Ventriculoperitoneal , Humanos , Derivación Ventriculoperitoneal/efectos adversos , Femenino , Masculino , Hidrocefalia/cirugía , Hidrocefalia/líquido cefalorraquídeo , Estudios Retrospectivos , Persona de Mediana Edad , Anciano , China/epidemiología , Adulto , Falla de Equipo
12.
Nat Commun ; 15(1): 3345, 2024 Apr 18.
Artículo en Inglés | MEDLINE | ID: mdl-38637571

RESUMEN

Exciton-polaritons (polaritons) resulting from the strong exciton-photon interaction stimulates the development of novel low-threshold coherent light sources to circumvent the ever-increasing energy demands of optical communications1-3. Polaritons from bound states in the continuum (BICs) are promising for Bose-Einstein condensation owing to their theoretically infinite quality factors, which provide prolonged lifetimes and benefit the polariton accumulations4-7. However, BIC polariton condensation remains limited to cryogenic temperatures ascribed to the small exciton binding energies of conventional material platforms. Herein, we demonstrated room-temperature BIC polariton condensation in perovskite photonic crystal lattices. BIC polariton condensation was demonstrated at the vicinity of the saddle point of polariton dispersion that generates directional vortex beam emission with long-range coherence. We also explore the peculiar switching effect among the miniaturized BIC polariton modes through effective polariton-polariton scattering. Our work paves the way for the practical implementation of BIC polariton condensates for integrated photonic and topological circuits.

13.
Nat Commun ; 15(1): 3203, 2024 Apr 13.
Artículo en Inglés | MEDLINE | ID: mdl-38615044

RESUMEN

Integrated circuit anti-counterfeiting based on optical physical unclonable functions (PUFs) plays a crucial role in guaranteeing secure identification and authentication for Internet of Things (IoT) devices. While considerable efforts have been devoted to exploring optical PUFs, two critical challenges remain: incompatibility with the complementary metal-oxide-semiconductor (CMOS) technology and limited information entropy. Here, we demonstrate all-silicon multidimensionally-encoded optical PUFs fabricated by integrating silicon (Si) metasurface and erbium-doped Si quantum dots (Er-Si QDs) with a CMOS-compatible procedure. Five in-situ optical responses have been manifested within a single pixel, rendering an ultrahigh information entropy of 2.32 bits/pixel. The position-dependent optical responses originate from the position-dependent radiation field and Purcell effect. Our evaluation highlights their potential in IoT security through advanced metrics like bit uniformity, similarity, intra- and inter-Hamming distance, false-acceptance and rejection rates, and encoding capacity. We finally demonstrate the implementation of efficient lightweight mutual authentication protocols for IoT applications by using the all-Si multidimensionally-encoded optical PUFs.

14.
Clin Neurol Neurosurg ; 239: 108248, 2024 04.
Artículo en Inglés | MEDLINE | ID: mdl-38507987

RESUMEN

BACKGROUND: The trajectory of early neurological changes in patients with acute ischemic stroke has been understudied. This study aimed to investigate the association between longitudinal trajectories of stroke severity and 90-day functional outcomes in patients with acute ischemic stroke receiving endovascular treatment. METHODS: We enrolled patients from a prospective, multicenter, randomized controlled trial. The stroke severity was assessed with the National Institute of Health Stroke Scale at the pre-procedure, 24 hours, and seven days after the procedure. Group-based trajectory modeling (GBTM) was used to identify trajectories of stroke severity. Multivariable logistic regression was performed to explore the association between stroke severity markers and 90-day functional outcomes. RESULTS: Of 218 enrolled patients, 127 (58.3%) had poor functional outcomes at 90 days. We identified three trajectories of stroke severity in the GBTM: stable symptom (38.1%), symptom deterioration (17.0%), and symptom improvement (44.9%). In multivariable analyses, trajectories of stroke severity were associated with an increased risk of poor functional outcomes (symptom improvement versus symptom deterioration: odds ratio, 0.007; 95% confidence interval, 0.001-0.040; P <0.001). Reclassification indexes revealed that trajectories of stroke severity would increase the predictive ability for poor functional outcomes at 90 days. CONCLUSION: After endovascular treatment, patients would follow one of three distinct trajectories of stroke severity. Symptom deterioration trajectory was associated with an increased risk of poor functional outcomes at 90 days. TRIAL REGISTRATION NUMBER: NCT04973332.


Asunto(s)
Isquemia Encefálica , Procedimientos Endovasculares , Accidente Cerebrovascular Isquémico , Accidente Cerebrovascular , Humanos , Accidente Cerebrovascular Isquémico/cirugía , Accidente Cerebrovascular Isquémico/complicaciones , Isquemia Encefálica/cirugía , Isquemia Encefálica/complicaciones , Estudios Prospectivos , Trombectomía/métodos , Resultado del Tratamiento , Accidente Cerebrovascular/cirugía , Accidente Cerebrovascular/diagnóstico , Procedimientos Endovasculares/métodos
15.
EuroIntervention ; 20(5): e312-e321, 2024 Mar 04.
Artículo en Inglés | MEDLINE | ID: mdl-38436369

RESUMEN

BACKGROUND: Intracranial atherosclerotic stenosis (ICAS), an important cause of stroke, is associated with a considerable stroke recurrence rate despite optimal medical treatment. Further assessment of the functional significance of ICAS is urgently needed to enable individualised treatment and, thus, improve patient outcomes. AIMS: We aimed to evaluate the haemodynamic significance of ICAS using the quantitative flow ratio (QFR) technique and to develop a risk stratification model for ICAS patients. METHODS: Patients with moderate to severe stenosis of the middle cerebral artery, as shown on angiography, were retrospectively enrolled. For haemodynamic assessment, the Murray law-based QFR (µQFR) was performed on eligible patients. Multivariate logistic regression models composed of µQFR and other risk factors were developed and compared for the identification of symptomatic lesions. Based on the superior model, a nomogram was established and validated by calibration. RESULTS: Among 412 eligible patients, symptomatic lesions were found in 313 (76.0%) patients. The µQFR outperformed the degree of stenosis in discriminating culprit lesions (area under the curve [AUC]: 0.726 vs 0.631; DeLong test p-value=0.001), and the model incorporating µQFR and conventional risk factors also performed better than that containing conventional risk factors only (AUC: 0.850 vs 0.827; DeLong test p-value=0.034; continuous net reclassification index=0.620, integrated discrimination improvement=0.057; both p<0.001). The final nomogram showed good calibration (p for Hosmer-Lemeshow test=0.102) and discrimination (C-statistic 0.850, 95% confidence interval: 0.812-0.883). CONCLUSIONS: The µQFR was significantly associated with symptomatic ICAS and outperformed the angiographic stenosis severity. The final nomogram effectively discriminated symptomatic lesions and may provide a useful tool for risk stratification in ICAS patients.


Asunto(s)
Arteriosclerosis Intracraneal , Accidente Cerebrovascular , Humanos , Constricción Patológica , Estudios Retrospectivos , Angiografía , Arteriosclerosis Intracraneal/diagnóstico por imagen
16.
Nat Commun ; 15(1): 1893, 2024 Feb 29.
Artículo en Inglés | MEDLINE | ID: mdl-38424438

RESUMEN

Exciton transport in two-dimensional Ruddlesden-Popper perovskite plays a pivotal role for their optoelectronic performance. However, a clear photophysical picture of exciton transport is still lacking due to strong confinement effects and intricate exciton-phonon interactions in an organic-inorganic hybrid lattice. Herein, we present a systematical study on exciton transport in (BA)2(MA)n-1PbnI3n+1 Ruddlesden-Popper perovskites using time-resolved photoluminescence microscopy. We reveal that the free exciton mobilities in exfoliated thin flakes can be improved from around 8 cm2 V-1 s-1 to 280 cm2V-1s-1 by anchoring the soft butyl ammonium cation with a polymethyl methacrylate network at the surface. The mobility of the latter is close to the theoretical limit of Mott-Ioffe-Regel criterion. Combining optical measurements and theoretical studies, it is unveiled that the polymethyl methacrylate network significantly improve the lattice rigidity resulting in the decrease of deformation potential scattering and lattice fluctuation at the surface few layers. Our work elucidates the origin of high exciton mobility in Ruddlesden-Popper perovskites and opens up avenues to regulate exciton transport in two-dimensional materials.

17.
Nat Commun ; 15(1): 960, 2024 Feb 02.
Artículo en Inglés | MEDLINE | ID: mdl-38307885

RESUMEN

Merging structural variations (SVs) at the population level presents a significant challenge, yet it is essential for conducting comprehensive genotypic analyses, especially in the era of pangenomics. Here, we introduce PanPop, a tool that utilizes an advanced sequence-aware SV merging algorithm to efficiently merge SVs of various types. We demonstrate that PanPop can merge and optimize the majority of multiallelic SVs into informative biallelic variants. We show its superior precision and lower rates of missing data compared to alternative software solutions. Our approach not only enables the filtering of SVs by leveraging multiple SV callers for enhanced accuracy but also facilitates the accurate merging of large-scale population SVs. These capabilities of PanPop will help to accelerate future SV-related studies.


Asunto(s)
Genómica , Programas Informáticos , Humanos , Algoritmos , Variación Estructural del Genoma , Genotipo , Genoma Humano
18.
Epidemiol Health ; 46: e2024005, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38404113

RESUMEN

OBJECTIVES: Atrial fibrillation (AF) contributes to stroke development and progression. We aimed to quantify the mediating role of AF in the causal associations between a wide range of risk factors and stroke via a Mendelian randomization (MR) framework. METHODS: We assessed the associations of 108 traits with stroke and its subtypes in a 2-sample univariable MR approach, then conducted a bidirectional MR analysis between these 108 traits and AF to evaluate the presence and direction of their causal associations. Finally, to further investigate the extent to which AF mediated the effects of eligible traits on stroke, we applied multivariable and 2-step MR techniques in a mediation analysis where outcomes were restricted to stroke types causally affected by AF (any stroke [AS], any ischemic stroke [AIS], and cardioembolic stroke [CES]). RESULTS: Among 108 traits, 42 were putatively causal for at least 1 stroke type; of these 42 traits, 20 that had no bidirectional relationship with AF were retained. Finally, 33 associations of 15 eligible traits were examined in the mediation analysis. The mediation analyses for AS, AIS, and CES each included 11 eligible traits. After AF adjustment, the direct effects of all traits on CES were attenuated to null (all p>0.05), while the associations with AS and AIS persisted for most traits (AF-mediated proportion: from 6.6% [95% confidence interval, 2.7 to 0.6] to 52.0% [95% confidence interval, 39.8 to 64.3]). CONCLUSIONS: The causal associations between all eligible traits and CES were largely mediated through AF, while most traits affected AS and AIS independently of AF.


Asunto(s)
Fibrilación Atrial , Accidente Cerebrovascular , Humanos , Fibrilación Atrial/epidemiología , Fibrilación Atrial/genética , Análisis de la Aleatorización Mendeliana , Factores de Riesgo , Accidente Cerebrovascular/epidemiología , Accidente Cerebrovascular/genética , Causalidad , Estudio de Asociación del Genoma Completo/métodos , Polimorfismo de Nucleótido Simple
19.
BMC Genomics ; 25(1): 139, 2024 Feb 03.
Artículo en Inglés | MEDLINE | ID: mdl-38310234

RESUMEN

BACKGROUND: CircRNAs are a class of noncoding RNAs with tissue- and development-specific expression characteristics. In many mammals, primordial follicle development begins in the embryonic stage. However, the study of circRNAs in primordial follicle development in mice has not been reported. RESULTS: In this study, ovaries were collected from mouse foetuses at 15.5 days post coitus (dpc) and 17.5 dpc, which are two key stages of primordial follicle development. A total of 4785 circRNAs were obtained by using RNA-seq. Of these, 83 differentially expressed circRNAs were identified. Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analyses showed that these differential circRNAs were mainly involved in the regulation of reproductive development. Through qRT-PCR, back-splice sequence detection and enzyme digestion protection experiments, we found that circ-009346, circ-014674, circ-017054 and circ-008296 were indeed circular. Furthermore, circ-009346, circ-014674 and circ-017054 were identified as three key circRNAs by analysing their expression in the ovaries of mice at different developmental stages. The circRNA-miRNA-mRNA interaction network was constructed and validated for target miRNA and mRNA using qRT-PCR. The interacting genes circ-009346, circ-014674, and circ-017054 were subjected to KEGG enrichment analysis. We found that circ-014674 may participate in the assembly and reserve of primordial follicles through oestrogen and the Janus kinase (JAK) signal transducer and activator of transcription (STAT) signalling pathway (JAK-SATA). Circ-009346 and circ-017054 may have similar functions and are involved in the activation and growth of primordial follicles through the mitogen-activated protein kinase (MAPK) and phosphoinositide 3-kinase (PI3K) signalling pathways. CONCLUSIONS: Based on our findings, three circRNAs associated with primordial follicle development were identified, and their potential mechanisms of regulating primordial follicle development were revealed. These findings will help us better understand the molecular mechanism of circRNAs in primordial follicles and provide important references and targets for the development of primordial follicles.


Asunto(s)
MicroARNs , ARN Circular , Femenino , Animales , Ratones , ARN Circular/genética , ARN Circular/metabolismo , Ovario/metabolismo , Fosfatidilinositol 3-Quinasas , MicroARNs/genética , ARN Mensajero , Mamíferos/genética
20.
Cereb Cortex ; 34(2)2024 01 31.
Artículo en Inglés | MEDLINE | ID: mdl-38212287

RESUMEN

This study aimed to explore the topographic features of thalamic subregions, functional connectomes and hierarchical organizations between thalamus and cortex in poststroke fatigue patients. We consecutively recruited 121 acute ischemic stroke patients (mean age: 59 years) and 46 healthy controls matched for age, sex, and educational level. The mean age was 59 years (range 19-80) and 38% of acute stroke patients were females. Resting-state functional and structural magnetic resonance imaging were conducted on all participants. The fatigue symptoms were measured using the Fatigue Severity Scale. The thalamic functional subdivisions corresponding to the canonical functional network were defined using the winner-take-all parcellation method. Thalamic functional gradients were derived using the diffusion embedding analysis. The results suggested abnormal functional connectivity of thalamic subregions primarily located in the temporal lobe, posterior cingulate gyrus, parietal lobe, and precuneus. The thalamus showed a gradual increase from the medial to the lateral in all groups, but the right thalamus shifted more laterally in poststroke fatigue patients than in non- poststroke fatigue patients. Poststroke fatigue patients also had higher gradient scores in the somatomotor network and the right medial prefrontal and premotor thalamic regions, but lower values in the right lateral prefrontal thalamus. The findings suggested that poststroke fatigue patients had altered functional connectivity and thalamocortical hierarchical organizations, providing new insights into the neural mechanisms of the thalamus.


Asunto(s)
Conectoma , Accidente Cerebrovascular Isquémico , Accidente Cerebrovascular , Femenino , Humanos , Adulto Joven , Adulto , Persona de Mediana Edad , Anciano , Anciano de 80 o más Años , Masculino , Conectoma/métodos , Accidente Cerebrovascular Isquémico/patología , Tálamo/patología , Imagen por Resonancia Magnética/métodos , Accidente Cerebrovascular/complicaciones , Accidente Cerebrovascular/diagnóstico por imagen , Accidente Cerebrovascular/patología , Fatiga/diagnóstico por imagen , Fatiga/etiología
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