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1.
Nano Lett ; 20(12): 8469-8475, 2020 Dec 09.
Artículo en Inglés | MEDLINE | ID: mdl-33174417

RESUMEN

Weyl semimetals have drawn considerable attention for their exotic topological properties in many research fields. When in combination with s-wave superconductors, the supercurrent can be carried by their topological surface channels, forming junctions mimicking the behavior of Majorana bound states. Here, we present a transmon-like superconducting quantum intereference device (SQUID) consisting of lateral junctions made of Weyl semimetal Td-MoTe2 and superconducting leads of niobium nitride (NbN). The SQUID is coupled to a readout cavity made of molybdenum rhenium (MoRe), whose response at high power reveals the existence of the constituting Josephson junctions (JJs). The loop geometry of the circuit allows the resonant frequency of the readout cavity to be tuned by the magnetic flux. We demonstrate a JJ made of MoTe2 and a flux-tunable transmon-like circuit based on Weyl semimetals. Our study provides a platform to utilize topological materials in SQUID-based quantum circuits for potential applications in quantum information processing.

2.
Nanotechnology ; 31(48): 485702, 2020 Nov 27.
Artículo en Inglés | MEDLINE | ID: mdl-32931469

RESUMEN

Silver phosphate (Ag3PO4, APO) has attracted intense attention as a visible-light-driven photocatalyst, but its large-scale application is limited by severe charge recombination and inevitable photo-corrosion. Various rational APO-based heterostructures composed of APO nanoparticles (NPs) and band-matched semiconductor support are designed to address the above issues. Nevertheless, the size, density, stability, and dispersion of APO NPs are critical challenges for the photocatalytic performance of APO-based photocatalysts. Here, three-dimensional (3D) self-assembled TiO2 hierarchical spheres (THS) prepared by a simple one-step hydrothermal method are employed as innovative support, and ultrafine high-density APO NPs with an average size of about 3 nm are successfully deposited and uniformly dispersed throughout THS to form hierarchical THS/APO composites. The novel THS/APO microstructure provides abundant reactive sites for photocatalytic reactions and promotes the photogenerated charge separation and transfer due to the ultrafine size of APO NPs and the TiO2/APO Type-II heterojunction. As a result, the THS/APO composites show significant improvement in photocatalytic activity and stability in methylene blue (MB) degradation. The reaction constant of THS/APO composites far exceeds that of either THS or APO, roughly 16 and 7 times higher than that of THS and APO under full-spectrum light, and 41 and 4 times higher under visible light. Our results strongly suggest new insights into the low-cost, large-scale application of high-efficiency APO-based photocatalyst.

3.
Adv Mater ; : e2403176, 2024 Jul 31.
Artículo en Inglés | MEDLINE | ID: mdl-39082207

RESUMEN

Hybrid devices that combine superconductors (S) and semiconductors (Sm) have attracted great attention due to the integration of the properties of both materials, which relies on the interface details and the resulting coupling strength and wavefunction hybridization. However, until now, none of the experiments have reported good control of the band alignment of the interface, as well as its tunability to the coupling and hybridization. Here, the interface is modified by inducing specific argon milling while maintaining its high quality, e.g., atomic connection, which results in a large induced superconducting gap and ballistic transport. By comparing with Schrödinger-Poisson calculations, it is proven that this method can vary the band bending/coupling strength and the electronic spatial distribution. In the strong coupling regime, the coexistence and tunability of crossed Andreev reflection and elastic co-tunneling-key ingredients for the Kitaev chain-are confirmed. This method is also generic for other materials and achieves a hard and huge superconducting gap in lead and indium antimonide nanowire (Pb-InSb) devices. Such a versatile method, compatible with the standard fabrication process and accompanied by the well-controlled modification of the interface, will definitely boost the creation of more sophisticated hybrid devices for exploring physics in solid-state systems.

4.
Nat Commun ; 14(1): 7647, 2023 Nov 23.
Artículo en Inglés | MEDLINE | ID: mdl-37996440

RESUMEN

The interplay between topology and interaction always plays an important role in condensed matter physics and induces many exotic quantum phases, while rare transition metal layered material (TMLM) has been proved to possess both. Here we report a TMLM Ta2Pd3Te5 has the two-dimensional second-order topology (also a quadrupole topological insulator) with correlated edge states - Luttinger liquid. It is ascribed to the unconventional nature of the mismatch between charge- and atomic- centers induced by a remarkable double-band inversion. This one-dimensional protected edge state preserves the Luttinger liquid behavior with robustness and universality in scale from micro- to macro- size, leading to a significant anisotropic electrical transport through two-dimensional sides of bulk materials. Moreover, the bulk gap can be modulated by the thickness, resulting in an extensive-range phase diagram for Luttinger liquid. These provide an attractive model to study the interaction and quantum phases in correlated topological systems.

5.
Arch Gerontol Geriatr ; 62: 30-5, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-26553484

RESUMEN

BACKGROUND: Sensory impairment affects an increasing number of elderly adults, with a negative psychological impact. Our objective was to examine the associations of visual and hearing impairment with subjective well-being (SWB), an important psychological concept defined by life satisfaction [LS], positive affect [PA], negative affect [NA], and affect balance [AB] among long-lived individuals (LLIs) over 95 years of age. METHODS: Data on 442 LLIs from the Rugao longevity cohort, a population-based study in Rugao, China, were analyzed. Graded classifications of visual and hearing impairment (none, mild, moderate, and severe) were constructed from self-reported items. Bivariate correlation and multiple regression analysis were performed to test the associations. RESULTS: Approximately 66.1% and 87.3% of the subjects reported varying degrees of visual and hearing impairment. Following the degree of vision impairment, LS, PA, and AB decreased linearly, whereas NA increased linearly (all p for trend<0.05). Vision was significantly related to LS (r=0.238, p<0.001), PA (r=0.142, p<0.01), NA (r=-0.157, p<0.001), and AB (r=0.206, p<0.001). After adjustment for multiple variables including functional ability, an important factor of SWB, the associations of vision impairment with LS, NA, and AB, while diminished, still existed. CONCLUSIONS: Visual impairment, but not hearing impairment, was independently associated with low SWB among LLIs, and functional ability may play a mediating role in the observed relationship. The findings indicate that rehabilitation targeted for those with reduced vision and functioning in long-lived populations may be important for promoting well-being and quality of life.


Asunto(s)
Pueblo Asiatico/psicología , Pérdida Auditiva/psicología , Longevidad , Calidad de Vida , Trastornos de la Visión/psicología , Baja Visión/psicología , Actividades Cotidianas , Anciano de 80 o más Años , China/epidemiología , Femenino , Pérdida Auditiva/epidemiología , Humanos , Masculino , Vigilancia de la Población , Trastornos de la Visión/epidemiología , Baja Visión/epidemiología
6.
Age (Dordr) ; 37(4): 9809, 2015 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-26178970

RESUMEN

Both activities of daily living (ADL) and some blood biomarkers (such as albumin) have been associated with mortality in very elderly people, but scarce data is available on the predictive performance of them in isolation or in combination, which is important for clinicians in decision making. Here, based on prospective mortality data over a 6-year follow-up period from 433 long-lived individuals (LLIs) aged 95+ years in the Rugao longevity cohort, we aimed to evaluate Cox proportional hazard ratios (HRs) and discriminative power (ROC curve) of 14 biomarkers and ADL for all-cause mortality. We found that six biomarkers (total triglyceride, albumin, low-density lipoprotein cholesterol, platelet count, lymphocyte count, and neutrophil count) were associated with mortality with a p < .10 in the univariate model. Significant associations of albumin and neutrophil count with mortality were observed when they were simultaneously included in a multivariate model, with HRs of 0.97 (95 % CI 0.94, 0.99; p = .005) and 1.09 (95 % CI 1.00, 1.18; p = .043). With respect to ADL, the corresponding HR was 1.10 (95 % CI 1.07, 1.14; p < .001). Low albumin (<40 g/L) combined with ADL dependent had a significantly increased mortality risk (HR = 2.19; 95 % CI 1.63, 2.95). Albumin and ADL separately showed good discriminative accuracies (area under the curve [AUC] = 0.68 and 0.66, respectively), and their combination had an increased predictive utility (AUC = 0.73). In conclusion, both albumin and ADL are efficient predictors of all-cause mortality in long-lived populations and their combination further increases discriminative power. The preliminary findings, if validated and translated, would help clinicians to identify the elderly people at varying mortality risk.


Asunto(s)
Actividades Cotidianas , Longevidad/fisiología , Mortalidad , Albúmina Sérica/metabolismo , Anciano de 80 o más Años , Biomarcadores/metabolismo , China , Estudios de Cohortes , Femenino , Evaluación Geriátrica , Humanos , Recuento de Leucocitos , Masculino , Neutrófilos , Valor Predictivo de las Pruebas , Curva ROC
7.
Age (Dordr) ; 37(1): 9750, 2015 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-25666573

RESUMEN

Genetic variants of whole mitochondrial DNA (mtDNA) that predispose to exceptional longevity need to be systematically identified and appraised. Here, we conducted a case-control study with 237 exceptional longevity subjects (aged 95-107) and 444 control subjects (aged 40-69) randomly recruited from a "longevity town"-the city of Rugao in China-to investigate the effects of mtDNA variants on exceptional longevity. We sequenced the entire mtDNA genomes of the 681 subjects using a next-generation platform and employed a complete mtDNA phylogenetic analytical strategy. We identified T3394C as a candidate that counteracts longevity, and we observed a higher load of private nonsynonymous mutations in the COX1 gene predisposing to female longevity. Additionally, for the first time, we identified several variants and new subhaplogroups related to exceptional longevity. Our results provide new clues for genetic mechanisms of longevity and shed light on strategies for evaluating rare mitochondrial variants that underlie complex traits.


Asunto(s)
Pueblo Asiatico/genética , ADN Mitocondrial/genética , Genoma Mitocondrial/genética , Longevidad/genética , Adulto , Anciano , Anciano de 80 o más Años , Estudios de Casos y Controles , China , Femenino , Haplotipos/genética , Humanos , Masculino , Persona de Mediana Edad
8.
Arch Gerontol Geriatr ; 60(2): 354-8, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-25541470

RESUMEN

BACKGROUND: CKD, a functional decline or break down of kidney, has been increasingly recognized as a public health problem and a predictor of poor outcomes (i.e., cardiovascular disease, dementia) and mortality among general populations. However, little is known regarding the prevalence and related factors of CKD among Chinese LLI over 95 years of age. METHODS: We used data of LLI from the Rugao longevity cohort, a population-based association study conducted in Rugao, a longevity town of China. CKD was defined as an estimated glomerular filtration rate (eGFR) of <60 mL/min/1.73 m2. Demographic exposures and biochemical markers were correlated with CKD. RESULTS: The prevalence of CKD among LLI in Rugao is 23.8%. Traditional risk factors for CKD among general population, such as hypertension, diabetes, and dyslipidemia, did not have associations with CKD. However, overweight, central adiposity, and hyperuricemia were associated with increased risk of CKD, with crude odds ratios of 2.41 (95% CI=1.23-4.69), 2.61 (95% CI=1.42-4.77), and 5.69 (95% CI=2.75-11.76), respectively. In addition, higher magnesium and filtration marker ß2 microglobulin (ß2M) were associated with CKD, with crude odds ratios of 2.47 (95% CI=1.38-4.43) and 16.38 (95% CI=6.76-39.64), respectively. CONCLUSIONS: We observe a high prevalence and unique related factors of CKD among the LLI in Rugao, which suggest that early screening and risk intervention of CKD are imperative to maintain a high quality of life and postpone the occurrence of poor outcomes.


Asunto(s)
Insuficiencia Renal Crónica/epidemiología , Anciano de 80 o más Años , China/epidemiología , Estudios de Cohortes , Femenino , Tasa de Filtración Glomerular , Humanos , Hiperuricemia/epidemiología , Magnesio/sangre , Masculino , Obesidad/epidemiología , Prevalencia , Factores de Riesgo , Microglobulina beta-2/sangre
9.
J Gerontol A Biol Sci Med Sci ; 70(5): 623-7, 2015 May.
Artículo en Inglés | MEDLINE | ID: mdl-25512568

RESUMEN

BACKGROUND: Several blood biomarkers have been linked to functional disability, a health problem in general populations. However, there are limited data for evaluating the potential association of biomarkers with functional disability in an extremely longevous (95+) population. METHODS: We used data from 420 extremely longevous individuals from the Rugao longevity cohort, a population-based association study conducted in Rugao, a longevity town in China. Functional disability was assessed by the Katz Index of Independence in activities of daily living. Blood biomarkers, including serum lipid, lipoprotein cholesterol, serum albumin, and lymphocyte count, were correlated with activities of daily living. RESULTS: Among extremely longevous women, following the degree of functional disability, serum albumin and lymphocyte count decreased significantly (all p for trend < .001). In a univariate model, serum albumin (ß = -0.279, p < .001), lymphocyte count (ß = -0.187, p < .001), and neutrophil count (ß = 0.140, p = .012) were found to be significantly associated with activities of daily living in women. After adjustment for other covariates, the significance remained. Notably, multivariate regression analysis revealed independent effects of all the three biomarkers on activities of daily living (ß = -0.242, -0.185, and 0.143, all p < .05). We did not observe any association in men. CONCLUSIONS: We found significant associations between serum albumin, lymphocyte count, and neutrophil count and physical disability even after adjustment for potential confounders in extremely longevous women, which call for further study. The findings provide preliminary but crucial clues for future studies specifically aimed at exploring the longitudinal relationships of interest before proceeding with interventions.


Asunto(s)
Biomarcadores/sangre , Evaluación de la Discapacidad , Evaluación Geriátrica , Longevidad , Actividades Cotidianas , Anciano de 80 o más Años , China , Femenino , Humanos , Masculino
10.
Age (Dordr) ; 36(3): 9632, 2014 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-24590626

RESUMEN

To examine the associations of cognitive and emotional facets (measured by life satisfaction [LS], positive affect [PA], negative affect [NA], and affect balance [AB]) of subjective well-being (SWB) with exceptional longevity (EL), we conducted a population-based study with 463 EL individuals (95+, EL group) recruited from a longevity town of Rugao, China (N = 755, with a response rate of 71.6 %), and 926 elderly individuals (60-69, elderly/control group). The population-based controls were sampled from the resident registry according to the gender ratio of the EL group. We found that the EL group had significantly higher levels of LS (30.74 vs. 28.93), PA (3.91 vs. 3.67), and AB (7.89 vs. 7.40) and a lower level of NA (1.02 vs. 1.27) than the elderly group. Multivariate logistic regression analysis revealed that higher levels of LS, PA, AB, and NA were significantly associated with EL, with odds ratios (ORs) of 1.98 (95 % CI, 1.36-2.89), 2.35 (95 % CI, 1.59-3.48), 2.56 (95 % CI, 1.75-3.75), and 0.50 (95 % CI, 0.33-0.74), respectively. Stratification analysis showed that the associations were significant in the healthy subsample, with the following ORs: LS = 2.31, PA = 2.53, AB = 3.05, and NA = 0.39. In conclusion, SWB, with high cognitive and emotional facets, was associated with EL in the healthy Rugao population. The findings imply that interventions that aim to improve elderly individuals' SWB may promote their quality of life and, ultimately, EL.


Asunto(s)
Afecto/fisiología , Emociones/fisiología , Longevidad/fisiología , Vigilancia de la Población/métodos , Calidad de Vida , Anciano , Anciano de 80 o más Años , China , Femenino , Humanos , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Medio Social
13.
PLoS One ; 4(7): e6423, 2009 Jul 29.
Artículo en Inglés | MEDLINE | ID: mdl-19641616

RESUMEN

BACKGROUND: Longevity is a multifactorial trait with a genetic contribution, and mitochondrial DNA (mtDNA) polymorphisms were found to be involved in the phenomenon of longevity. METHODOLOGY/PRINCIPAL FINDINGS: To explore the effects of mtDNA haplogroups on the prevalence of extreme longevity (EL), a population based case-control study was conducted in Rugao--a prefecture city in Jiangsu, China. Case subjects include 463 individuals aged > or = 95 yr (EL group). Control subjects include 926 individuals aged 60-69 years (elderly group) and 463 individuals aged 40-49 years (middle-aged group) randomly recruited from Rugao. We observed significant reduction of M9 haplogroups in longevity subjects (0.2%) when compared with both elderly subjects (2.2%) and middle-aged subjects (1.7%). Linear-by-linear association test revealed a significant decreasing trend of N9 frequency from middle-aged subjects (8.6%), elderly subjects (7.2%) and longevity subjects (4.8%) (p = 0.018). In subsequent analysis stratified by gender, linear-by-linear association test revealed a significant increasing trend of D4 frequency from middle-aged subjects (15.8%), elderly subjects (16.4%) and longevity subjects (21.7%) in females (p = 0.025). Conversely, a significant decreasing trend of B4a frequency was observed from middle-aged subjects (4.2%), elderly subjects (3.8%) and longevity subjects (1.7%) in females (p = 0.045). CONCLUSIONS: Our observations support the association of mitochondrial DNA haplogroups with exceptional longevity in a Chinese population.


Asunto(s)
ADN Mitocondrial/genética , Haplotipos , Longevidad , Anciano , China , Femenino , Humanos , Masculino , Persona de Mediana Edad , Polimorfismo de Nucleótido Simple
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