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1.
Philos Trans R Soc Lond B Biol Sci ; 378(1885): 20220223, 2023 09 11.
Artículo en Inglés | MEDLINE | ID: mdl-37482774

RESUMEN

Excess weight gained during the early years and, in particular, rapid weight gain in the first 2 years of life, are a major risk factors for adult obesity. The growing consensus is that childhood obesity develops from a complex interaction between genetic susceptibility and exposure to an 'obesogenic' environment. Behavioural susceptibility theory (BST) was developed to explain the nature of this gene-environment interaction, and why the 'obesogenic' environment does not affect all children equally. It hypothesizes that inherited variation in appetite, which is present from birth, determines why some infants and children overeat, and others do not, in response to environmental opportunity. That is, those who inherit genetic variants promoting an avid appetite are vulnerable to overeating and developing obesity, while those who are genetically predisposed to have a smaller appetite and lower interest in food are protected from obesity-or even at risk of being underweight. We review the breadth of research to-date that has contributed to the evidence base for BST, focusing on early life, and discuss implications and future directions for research and theory. This article is part of a discussion meeting issue 'Causes of obesity: theories, conjectures and evidence (Part I)'.


Asunto(s)
Apetito , Obesidad Infantil , Niño , Humanos , Apetito/genética , Predisposición Genética a la Enfermedad , Conducta Alimentaria/fisiología , Interacción Gen-Ambiente
2.
Acad Radiol ; 30(7): 1472-1480, 2023 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-36323613

RESUMEN

RATIONALE AND OBJECTIVES: To evaluate the effectiveness of an artificial intelligence (AI) in radiology literacy course on participants from nine radiology residency programs in the Southeast and Mid-Atlantic United States. MATERIALS AND METHODS: A week-long AI in radiology course was developed and included participants from nine radiology residency programs in the Southeast and Mid-Atlantic United States. Ten 30 minutes lectures utilizing a remote learning format covered basic AI terms and methods, clinical applications of AI in radiology by four different subspecialties, and special topics lectures on the economics of AI, ethics of AI, algorithm bias, and medicolegal implications of AI in medicine. A proctored hands-on clinical AI session allowed participants to directly use an FDA cleared AI-assisted viewer and reporting system for advanced cancer. Pre- and post-course electronic surveys were distributed to assess participants' knowledge of AI terminology and applications and interest in AI education. RESULTS: There were an average of 75 participants each day of the course (range: 50-120). Nearly all participants reported a lack of sufficient exposure to AI in their radiology training (96.7%, 90/93). Mean participant score on the pre-course AI knowledge evaluation was 8.3/15, with a statistically significant increase to 10.1/15 on the post-course evaluation (p= 0.04). A majority of participants reported an interest in continued AI in radiology education in the future (78.6%, 22/28). CONCLUSION: A multi-institutional AI in radiology literacy course successfully improved AI education of participants, with the majority of participants reporting a continued interest in AI in radiology education in the future.


Asunto(s)
Inteligencia Artificial , Radiología , Humanos , Alfabetización , Radiología/educación , Algoritmos , Escolaridad
3.
J Nutr Health Aging ; 26(6): 615-620, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35718871

RESUMEN

BACKGROUND: Recent evidence point towards an interaction between omega-3 (n-3) polyunsaturated fatty acids (PUFA) and plasma homocysteine (Hcy). OBJECTIVES: This study tested the hypothesis that effects of red blood cell n-3 PUFA are modified according to baseline plasma Hcy in the large Mulit-domain Alzheimer Prevention Trial (MAPT) throughout the 3-years of treatment with an additional 2 years of observational follow-up. DESIGN: Experimental study. PARTICIPANTS: From the 1680 participants that were randomized in the four groups of the MAPT study (two of which received n-3 PUFA, the other two without n-3 PUFA), 782 were selected because they had baseline data on both Hcy and n-3 PUFA. MEASUREMENTS: Cognitive performance was measured with a broad set of cognitive tests including free and total recall of the cued selective reminding test, digit symbol substitution test, category naming test and Trail-making tests (TMT-A and B) and Clinical dementia rating scale. RESULTS: We found a significant association between TMT-A and red blood cell n-3 PUFA levels in participants with Hcy values ≤16.8 µMol/L after adjustments at baseline (Estimate: -1.3, 95% CI: -2.3; -0.3, p=0.01). Additionally, participants with high Hcy values had a significant worsening after adjustments in TMT-B after a 5-year n-3 PUFA supplementation, compared to low levels of Hcy (Mean difference: 34.8, 95% CI: 7.8;61.7). CONCLUSION: This study shows that Hcy levels could modify the association between red blood cell n-3 PUFA and executive function. People with high Hcy may benefit less from a n-3 PUFA supplementation to prevent cognitive decline.


Asunto(s)
Disfunción Cognitiva , Ácidos Grasos Omega-3 , Anciano , Cognición , Disfunción Cognitiva/tratamiento farmacológico , Disfunción Cognitiva/prevención & control , Suplementos Dietéticos , Ácidos Grasos Omega-3/farmacología , Ácidos Grasos Omega-3/uso terapéutico , Homocisteína , Humanos
4.
J Nutr Health Aging ; 25(10): 1154-1160, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34866142

RESUMEN

BACKGROUND AND OBJECTIVES: A randomized placebo-controlled trial found a significant negative interaction between aspirin and B vitamins in cognitive functioning in older people with mild cognitive impairment (MCI). To validate this finding, we pooled data of this trial with that of a similar B-vitamin trial (VITACOG) to examine the effectiveness of B vitamins and their interactions with aspirin in improving global cognitive functioning and slowing brain atrophy in older people with MCI. DESIGN: Pooled post-hoc analyses of two randomized placebo-controlled trials. PARTICIPANTS: In total, 545 older people with MCI were included in the study. INTERVENTION: Placebo or B-vitamin supplements (vitamin B12, folic acid with or without vitamin B6) for 24 months. MEASUREMENTS: The primary outcome was the Clinical Dementia Rating scale-global score (CDR-global). The secondary outcomes were CDR-sum of box score (CDR-SOB), memory Z-score, executive function Z-score, and whole brain atrophy rate. RESULTS: 71 (26.2%) and 83 (30.3%) subjects in the active and placebo group respectively were aspirin users. Overall, B vitamins reduced whole brain atrophy rate significantly (P = 0.003), but did not have significant effect on CDR-global, CDR-SOB, memory and executive function. Aspirin use had significant negative interaction effects on B vitamins in CDR-global and CDR-SOB (Beta = 0.993, P = 0.038, and Beta = 0.583, P = 0.009, respectively), but not in memory or executive function Z-scores. Among aspirin non-users, B-vitamin group subjects had more favourable changes in CDR-global and CDR-SOB (P = 0.019 and 0.057, respectively). B vitamins significantly slowed brain atrophy in aspirin non-users (P = 0.001), but not in aspirin users, though the interaction term was not significant (Beta = 0.192, P = 0.276). CONCLUSION: In older people with MCI, B vitamins had significantly favourable effects on global cognitive functioning and whole brain atrophy rate in those who were not taking aspirin, but not in aspirin users.


Asunto(s)
Disfunción Cognitiva , Complejo Vitamínico B , Anciano , Aspirina/uso terapéutico , Cognición , Disfunción Cognitiva/complicaciones , Disfunción Cognitiva/tratamiento farmacológico , Humanos , Ensayos Clínicos Controlados Aleatorios como Asunto , Vitamina B 12/farmacología , Vitamina B 12/uso terapéutico , Complejo Vitamínico B/farmacología , Complejo Vitamínico B/uso terapéutico
5.
J Intern Med ; 290(4): 826-854, 2021 10.
Artículo en Inglés | MEDLINE | ID: mdl-33660358

RESUMEN

We have reviewed the literature and have identified more than 100 diseases or conditions that are associated with raised concentrations of plasma total homocysteine. The commonest associations are with cardiovascular diseases and diseases of the central nervous system, but a large number of developmental and age-related conditions are also associated. Few other disease biomarkers have so many associations. The clinical importance of these associations becomes especially relevant if lowering plasma total homocysteine by B vitamin treatment can prevent disease and so improve health. Five diseases can at least in part be prevented by lowering total homocysteine: neural tube defects, impaired childhood cognition, macular degeneration, primary stroke, and cognitive impairment in the elderly. We conclude from our review that total homocysteine values in adults of 10 µmol/L or below are probably safe, but that values of 11 µmol/L or above may justify intervention. Homocysteine is more than a disease biomarker: it is a guide for the prevention of disease.


Asunto(s)
Homocisteína/sangre , Complejo Vitamínico B , Adulto , Anciano , Biomarcadores , Niño , Disfunción Cognitiva/prevención & control , Humanos , Degeneración Macular/prevención & control , Defectos del Tubo Neural/prevención & control , Accidente Cerebrovascular/prevención & control , Complejo Vitamínico B/uso terapéutico
6.
Sensors (Basel) ; 19(19)2019 Sep 29.
Artículo en Inglés | MEDLINE | ID: mdl-31569477

RESUMEN

There is an urgent need to fulfill future energy demands for micro and nanoelectronics. This work outlines a number of important design features for carbon-based microsupercapacitors, which enhance both their performance and integration potential and are critical for complimentary metal oxide semiconductor (CMOS) compatibility. Based on these design features, we present CMOS-compatible, graphene-based microsupercapacitors that can be integrated at the back end of the line of the integrated circuit fabrication. Electrode materials and their interfaces play a crucial role for the device characteristics. As such, different carbon-based materials are discussed and the importance of careful design of current collector/electrode interfaces is emphasized. Electrode adhesion is an important factor to improve device performance and uniformity. Additionally, doping of the electrodes can greatly improve the energy density of the devices. As microsupercapacitors are engineered for targeted applications, device scaling is critically important, and we present the first steps toward general scaling trends. Last, we outline a potential future integration scheme for a complete microsystem on a chip, containing sensors, logic, power generation, power management, and power storage. Such a system would be self-powering.

9.
Allergy ; 73(1): 125-136, 2018 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-28745029

RESUMEN

BACKGROUND: Allergy and allergic asthma are significant health burdens in developed countries and are increasing in prevalence. Dendritic cells (DCs) initiate immune responses to common aeroallergens, and ADAM10 has been demonstrated to be important for the development of adaptive responses. This study's objective was to understand the role of ADAM10 on DCs in the development of allergic and anaphylactic responses. METHODS: In this study, we used mouse models of allergic airway inflammation (house dust mice and Alternaria alternata) and OVA-induced models of active anaphylaxis to determine the DC-specific function of ADAM10 and Notch signaling. To examine TH 1 and TH 17 immunity infection with Anaplasma phagocytophilum and Citrobacter rodentium respectively, were used. RESULTS: Mice, which have ADAM10 deleted from DCs, have dramatic reductions in IgE production and do not develop significant TH 2 immune responses. Further, ADAM10DC-/- mice are resistant to IgE-mediated anaphylaxis. This response is selective for TH 2 immunity as TH 1 and TH 17 immunity is largely unaffected. Notch1, a known ADAM10 substrate, when knocked out of DCs (Notch1DC-/- ) demonstrated a similar reduction in anaphylaxis and IgE. Without ADAM10 and Notch1 signaling, DCs were unable to make cytokines that stimulate TH 2 cells and cytokines. Anaphylaxis and allergic lung inflammation were restored in ADAM10DC-/- with the overexpression of the Notch1-intracellular domain, confirming the role of Notch signaling. CONCLUSIONS: Targeting ADAM10 and Notch1 on DCs represent a novel strategy for modulating TH 2 immune responses and IgE production.


Asunto(s)
Proteína ADAM10/metabolismo , Secretasas de la Proteína Precursora del Amiloide/metabolismo , Células Dendríticas/inmunología , Células Dendríticas/metabolismo , Inmunoglobulina E/inmunología , Proteínas de la Membrana/metabolismo , Receptor Notch1/metabolismo , Proteína ADAM10/genética , Secretasas de la Proteína Precursora del Amiloide/genética , Anafilaxia/inmunología , Anafilaxia/metabolismo , Animales , Biomarcadores , Modelos Animales de Enfermedad , Expresión Génica , Hipersensibilidad/inmunología , Hipersensibilidad/metabolismo , Inmunoglobulina G/sangre , Inmunoglobulina G/inmunología , Interleucina-6/genética , Interleucina-6/metabolismo , Factor 4 Similar a Kruppel , Factores de Transcripción de Tipo Kruppel/genética , Factores de Transcripción de Tipo Kruppel/metabolismo , Proteínas de la Membrana/genética , Ratones , Ratones Noqueados , Pyroglyphidae/inmunología , Receptor Notch1/genética , Transducción de Señal , Células TH1/inmunología , Células TH1/metabolismo , Células Th17/inmunología , Células Th17/metabolismo , Células Th2/inmunología , Células Th2/metabolismo
11.
Phys Rev Lett ; 118(13): 139902, 2017 Mar 31.
Artículo en Inglés | MEDLINE | ID: mdl-28409949

RESUMEN

This corrects the article DOI: 10.1103/PhysRevLett.117.163002.

12.
Oecologia ; 183(3): 701-713, 2017 03.
Artículo en Inglés | MEDLINE | ID: mdl-28105521

RESUMEN

While interspecific competition is prevalent in natural systems, we do not yet understand how it can influence an individual's phenotype within its lifetime and how this might affect performance. Morphology and swimming performance are two important fitness-related traits in fishes. Both traits are essential in acquiring and defending resources as well as avoiding predation. Here, we examined if interspecific competition could induce changes in morphology and affect the swimming performance of two strains of juvenile Atlantic salmon (Salmo salar). We imposed competitive scenarios on the fish using artificial streams containing different combinations of four interspecific competitors. Exposure to interspecific competitors induced morphological changes over time, through the development of deeper bodies, whereas controls free of interspecific competitors developed more fusiform body shapes. Furthermore, swimming performance was correlated to fusiform morphologies and was weaker for Atlantic salmon in competitive scenarios vs. CONTROLS: This implies that interspecific competition has direct effects on these fitness-related traits in Atlantic salmon. To the best of our knowledge, this is the first time that morphology, an important fitness-related trait linked to swimming performance, has been shown to be negatively impacted through interactions with an interspecific competitor.


Asunto(s)
Fenotipo , Natación , Animales , Conducta Competitiva , Conducta Predatoria , Salmo salar
13.
Colorectal Dis ; 19(7): 681-689, 2017 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-27943522

RESUMEN

AIM: Advances in laparoscopic techniques combined with enhanced recovery pathways have led to faster recuperation and discharge after colorectal surgery. Peripheral nerve blockade using transversus abdominis plane (TAP) blocks reduce opioid requirements and provide better analgesia for laparoscopic colectomies than do inactive controls. This double-blind randomized study was performed to compare TAP blocks using bupivacaine with standardized wound infiltration with local anaesthetic (LA). METHOD: Seventy-one patients were randomized to receive either TAP block or wound infiltration. The TAP blocks were performed by experienced anaesthetists who used ultrasound guidance to deliver 40 ml of 0.25% bupivacaine post-induction into the transverse abdominis plane. In the control group, 40 ml of 0.25% bupivacaine was injected around the trocar and the extraction site by the surgeon. Both groups received patient-controlled analgesia (PCA) with intravenous morphine. Patients and nursing staff assessed pain scores 6, 12, 24 and 48 h after surgery. The primary outcome was overall morphine use in the first 48 h. RESULTS: Of the 71 patients, 20 underwent a right hemicolectomy and 51 a high anterior resection. The modified intention-to-treat analysis showed no significant differences in overall morphine use [47.3 (36.2-58.5) mg vs 46.7 (36.2-57.3) mg; mean (95% CI), P = 0.8663] in the first 48 h. Pain scores were similar at 6, 12, 24 and 48 h. No differences were found regarding time to mobilization, resumption of diet and length of hospital stay. CONCLUSION: In elective laparoscopic colectomies, standardized wound infiltration with LA has the same analgesic effect as TAP blocks post-induction using bupivacaine at 48 h.


Asunto(s)
Anestésicos Locales/administración & dosificación , Colectomía/efectos adversos , Laparoscopía/efectos adversos , Bloqueo Nervioso/métodos , Dolor Postoperatorio/tratamiento farmacológico , Anciano , Bupivacaína/administración & dosificación , Colectomía/métodos , Método Doble Ciego , Femenino , Humanos , Laparoscopía/métodos , Masculino , Persona de Mediana Edad , Dimensión del Dolor , Dolor Postoperatorio/etiología , Herida Quirúrgica , Resultado del Tratamiento , Ultrasonografía Intervencional/métodos
14.
Phys Rev Lett ; 117(16): 163002, 2016 Oct 14.
Artículo en Inglés | MEDLINE | ID: mdl-27792360

RESUMEN

Hydrogen bonding interactions between biological chromophores and their surrounding protein and solvent environment significantly affect the photochemical pathways of the chromophore and its biological function. A common first step in the dynamics of these systems is excited state proton transfer between the noncovalently bound molecules, which stabilizes the system against dissociation and principally alters relaxation pathways. Despite such fundamental importance, studying excited state proton transfer across a hydrogen bond has proven difficult, leaving uncertainties about the mechanism. Through time-resolved photoelectron imaging measurements, we demonstrate how the addition of a single hydrogen bond and the opening of an excited state proton transfer channel dramatically changes the outcome of a photochemical reaction, from rapid dissociation in the isolated chromophore to efficient stabilization and ground state recovery in the hydrogen bonded case, and uncover the mechanism of excited state proton transfer at a hydrogen bond, which follows sequential hydrogen and charge transfer processes.

15.
Anaesthesia ; 71(10): 1144-52, 2016 10.
Artículo en Inglés | MEDLINE | ID: mdl-27501155

RESUMEN

Concerns have been raised about the effects on cognition of anaesthesia for surgery, especially in elderly people. We recorded cognitive decline in a cohort of 394 people (198 women) with median (IQR) age at recruitment of 72.6 (66.6-77.8) years, of whom 109 had moderate or major surgery during a median (IQR) follow-up of 4.1 (2.0-7.6) years. Cognitive decline was more rapid in people who on recruitment were: older, p = 0.0003; male, p = 0.027; had worse cognition, p < 0.0001; or carried the ε4 allele of apoliprotein E (APOEε4), p = 0.008; and after an operation if cognitive impairment was already diagnosed, p = 0.0001. Cognitive decline appears to accelerate after surgery in elderly patients diagnosed with cognitive impairment, but not other elderly patients.


Asunto(s)
Envejecimiento/psicología , Anestesia/efectos adversos , Disfunción Cognitiva/epidemiología , Evaluación Geriátrica/estadística & datos numéricos , Complicaciones Posoperatorias/epidemiología , Factores de Edad , Anciano , Estudios de Cohortes , Femenino , Estudios de Seguimiento , Humanos , Masculino , Memoria , Pruebas Neuropsicológicas/estadística & datos numéricos , Factores de Riesgo , Factores Sexuales
16.
Nanoscale ; 7(30): 13096-104, 2015 Aug 14.
Artículo en Inglés | MEDLINE | ID: mdl-26176739

RESUMEN

Vertical graphene-based device concepts that rely on quantum mechanical tunneling are intensely being discussed in the literature for applications in electronics and optoelectronics. In this work, the carrier transport mechanisms in semiconductor-insulator-graphene (SIG) capacitors are investigated with respect to their suitability as electron emitters in vertical graphene base transistors (GBTs). Several dielectric materials as tunnel barriers are compared, including dielectric double layers. Using bilayer dielectrics, we experimentally demonstrate significant improvements in the electron injection current by promoting Fowler-Nordheim tunneling (FNT) and step tunneling (ST) while suppressing defect mediated carrier transport. High injected tunneling current densities approaching 10(3) A cm(-2) (limited by series resistance), and excellent current-voltage nonlinearity and asymmetry are achieved using a 1 nm thick high quality dielectric, thulium silicate (TmSiO), as the first insulator layer, and titanium dioxide (TiO2) as a high electron affinity second layer insulator. We also confirm the feasibility and effectiveness of our approach in a full GBT structure which shows dramatic improvement in the collector on-state current density with respect to the previously reported GBTs. The device design and the fabrication scheme have been selected with future CMOS process compatibility in mind. This work proposes a bilayer tunnel barrier approach as a promising candidate to be used in high performance vertical graphene-based tunneling devices.

17.
Rev Sci Instrum ; 86(4): 046105, 2015 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-25933903

RESUMEN

Evaluating the radiation stability of mineral phases is a vital research challenge when assessing the performance of the materials employed in a Geological Disposal Facility for radioactive waste. This report outlines the setup and methodology for efficiently allowing the determination of the dose dependence of damage to a mineral from a single ion irradiated sample. The technique has been deployed using the Dalton Cumbrian Facility's 5 MV tandem pelletron to irradiate a suite of minerals with a controlled α-particle ((4)He(2+)) beam. Such minerals are proxies for near-field clay based buffer material surrounding radioactive canisters, as well as the sorbent components of the host rock.

18.
Curr Oncol ; 22(1): 64-7, 2015 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-25684990

RESUMEN

Metastatic castration-resistant prostate cancer is now commonly treated with abiraterone, an orally administered chronic medication. Although abiraterone has certain advantages over docetaxel-based therapy, patients are now responsible for ensuring optimal adherence to their medication. To our knowledge, adherence to abiraterone in a real-world setting has never been described. The objective of the present study was to measure adherence to abiraterone among the first patients to receive the drug in Saskatchewan. Electronic pharmacy claims were obtained from the Saskatchewan Cancer Agency after removal of patient names and identifiers. All patients with at least 1 dispensation for abiraterone between August 2011 and October 2013 were eligible. The primary endpoint was the percentage of patients achieving optimal adherence at 6 months, defined as a medication possession ratio (mpr) of 80% or better. During the study period, 141 patients received abiraterone, among whom 86 could be followed for at least 6 months. Optimal adherence was achieved in 82.6% of patients (71 of 86) at 6 months, with 79.1% achieving a mpr of at least 90%. Of patients with available follow-up to 1 year, 81.6% (31 of 38) maintained optimal adherence during the entire period.

19.
Lett Appl Microbiol ; 60(4): 334-40, 2015 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-25422036

RESUMEN

UNLABELLED: Controlling spread of human pathogens on fresh produce is a top priority for public health reasons. Isolation of compounds from agricultural waste that would control spread of human pathogens was explored using Salmonella enterica serovar Typhimurium as a model organism. In the environment, micro-organisms migrate as a 'community' especially when they move on moist surfaces. This type of motility is characterized as swarming motility. We examined extracts from agricultural waste such as soya bean husk, peels of orange, pineapple, avocado and pomegranate for antiswarming activity. Avocado and pineapple peels showed moderate (~40%) inhibition of swarming motility while pomegranate peel extract had high antiswarming activity (~85% inhibition) and was examined in further detail. Although the pomegranate peel extract was acidic, swarm-inhibitory activity was not due to low pH and the peel extract did not inhibit growth of Salmonella. Among the key swarm motility regulatory genes, class II (fliF, fliA, fliT and fliZ) and class III (fliC and fliM) regulators were downregulated upon exposure to pomegranate peel extract. Pomegranate peels offer great potential as a bioactive repellent for pathogenic micro-organisms on moist surfaces. SIGNIFICANCE AND IMPACT OF THE STUDY: Controlling the spread of food-borne pathogens in moist environments is an important microbial food safety issue. Isolation of compounds from agricultural waste (such as fruit peels) that would control spread of human pathogens was explored using Salmonella enterica serovar Typhimurium as a model organism. Pomegranate peels offer great potential as a bioactive repellent for pathogenic micro-organisms.


Asunto(s)
Antibacterianos/química , Lythraceae/química , Lythraceae/microbiología , Extractos Vegetales/química , Salmonella typhimurium/metabolismo , Ananas/química , Ananas/microbiología , Citrus sinensis/química , Citrus sinensis/microbiología , Flagelos/genética , Flagelos/metabolismo , Humanos , Pruebas de Sensibilidad Microbiana , Persea/química , Persea/microbiología , Salmonella typhimurium/genética , Glycine max/química , Glycine max/microbiología , Residuos/análisis
20.
Nano Lett ; 13(7): 3237-42, 2013 Jul 10.
Artículo en Inglés | MEDLINE | ID: mdl-23786215

RESUMEN

Monolayer graphene exhibits exceptional electronic and mechanical properties, making it a very promising material for nanoelectromechanical devices. Here, we conclusively demonstrate the piezoresistive effect in graphene in a nanoelectromechanical membrane configuration that provides direct electrical readout of pressure to strain transduction. This makes it highly relevant for an important class of nanoelectromechanical system (NEMS) transducers. This demonstration is consistent with our simulations and previously reported gauge factors and simulation values. The membrane in our experiment acts as a strain gauge independent of crystallographic orientation and allows for aggressive size scalability. When compared with conventional pressure sensors, the sensors have orders of magnitude higher sensitivity per unit area.


Asunto(s)
Conductometría/instrumentación , Grafito/química , Sistemas Microelectromecánicos/instrumentación , Nanopartículas/química , Nanotecnología/instrumentación , Transductores de Presión , Módulo de Elasticidad , Diseño de Equipo , Análisis de Falla de Equipo , Nanopartículas/ultraestructura , Presión
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