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1.
Diabetes Obes Metab ; 24(11): 2138-2147, 2022 11.
Artículo en Inglés | MEDLINE | ID: mdl-35676798

RESUMEN

AIMS: To confirm the reno-protective effects of sodium-glucose cotransporter-2 (SGLT2) inhibitors compared with dipeptidyl peptidase-4 (DPP-4) inhibitors on the onset and progression of chronic kidney disease (CKD) in routine clinical practice. MATERIALS AND METHODS: We conducted a retrospective cohort study using the Clinical Practice Research Datalink Aurum database linked to Hospital Episode Statistics. The primary outcome was risk of the composite CKD endpoint based on the recent consensus guidelines for kidney disease: >40% decline in estimated glomerular filtration rate (eGFR), kidney death or end-stage kidney disease (ESKD; a composite of kidney transplantation, maintenance of dialysis, sustained low eGFR <15 ml/min/1.73m² or diagnosis of ESKD). Secondary outcomes were components of the composite CKD endpoint, analysed separately. Patients were propensity-score-matched 1:1 for SGLT2 inhibitor versus DPP-4 inhibitor use. RESULTS: A total of 131 824 people with type 2 diabetes (T2D) were identified; 79.0% had no known history of CKD. During a median follow-up of 2.1 years, SGLT2 inhibitor initiation was associated with lower risk of progression to composite kidney endpoints than DPP-4 inhibitor initiation (7.48 vs. 11.77 events per 1000 patient-years, respectively). Compared with DPP-4 inhibitor initiation, SGLT2 inhibitor initiation was associated with reductions in the primary composite CKD endpoint (hazard ratio [HR] 0.64, 95% confidence interval [CI] 0.56-0.74), all-cause mortality (HR 0.74, 95% CI 0.64-0.86) and ESKD (HR 0.37, 95% CI 0.25-0.55), reduced the rate of sustained low eGFR (HR 0.33, 95% CI 0.19-0.57), and reduced diagnoses of ESKD in primary care (HR 0.04, 95% CI 0.01-0.18). Results were consistent across subgroup and sensitivity analyses. CONCLUSIONS: In adults with T2D, initiation of an SGLT2 inhibitor was associated with a significantly reduced risk of CKD progression and death compared with initiation of a DPP-4 inhibitor.


Asunto(s)
Diabetes Mellitus Tipo 2 , Inhibidores de la Dipeptidil-Peptidasa IV , Insuficiencia Renal Crónica , Inhibidores del Cotransportador de Sodio-Glucosa 2 , Adulto , Diabetes Mellitus Tipo 2/complicaciones , Diabetes Mellitus Tipo 2/tratamiento farmacológico , Inhibidores de la Dipeptidil-Peptidasa IV/uso terapéutico , Dipeptidil-Peptidasas y Tripeptidil-Peptidasas , Glucosa , Humanos , Hipoglucemiantes , Insuficiencia Renal Crónica/complicaciones , Insuficiencia Renal Crónica/tratamiento farmacológico , Insuficiencia Renal Crónica/epidemiología , Estudios Retrospectivos , Sodio , Transportador 2 de Sodio-Glucosa , Inhibidores del Cotransportador de Sodio-Glucosa 2/uso terapéutico , Reino Unido/epidemiología
2.
Chem Soc Rev ; 51(2): 650-671, 2022 Jan 24.
Artículo en Inglés | MEDLINE | ID: mdl-34931635

RESUMEN

The piezoelectric effect, mechanical-to-electrical and electrical-to-mechanical energy conversion, is highly beneficial for functional and responsive electronic devices. To fully exploit this property, miniaturization of piezoelectric materials is the subject of intense research. Indeed, select atomically thin 2D materials strongly exhibit the piezoelectric effect. The family of 2D crystals consists of over 7000 chemically distinct members that can be further manipulated in terms of strain, functionalization, elemental substitution (i.e. Janus 2D crystals), and defect engineering to induce a piezoelectric response. Additionally, most 2D crystals can stack with other similar or dissimilar 2D crystals to form a much greater number of complex 2D heterostructures whose properties are quite different to those of the individual constituents. The unprecedented flexibility in tailoring 2D crystal properties, coupled with their minimal thickness, make these emerging highly attractive for advanced piezoelectric applications that include pressure sensing, piezocatalysis, piezotronics, and energy harvesting. This review summarizes literature on piezoelectricity, particularly out-of-plane piezoelectricity, in the vast family of 2D materials as well as their heterostructures. It also describes methods to induce, enhance, and control the piezoelectric properties. The volume of data and role of machine learning in predicting piezoelectricity is discussed in detail, and a prospective outlook on the 2D piezoelectric field is provided.


Asunto(s)
Electricidad , Electrónica , Estudios Prospectivos
3.
Diabetes Obes Metab ; 23(10): 2207-2214, 2021 10.
Artículo en Inglés | MEDLINE | ID: mdl-33973690

RESUMEN

AIM: To assess if sodium-glucose co-transporter-2 inhibitors (SGLT2is) reduce the risk of all-cause mortality, cardiovascular death and hospitalization for heart failure (HF) or chronic kidney disease (CKD) to a greater extent than dipeptidyl peptidase-4 inhibitors (DPP4is) in people with type 2 diabetes (T2D) with or without established cardiovascular and/or renal disease (CVRD). METHODS: This retrospective cohort study propensity-matched 24 438 patients receiving an SGLT2i 1:1 to a patient receiving a DDP4i, stratified based on the presence of CVRD. The primary outcomes were the time to each of the following: all-cause mortality, cardiovascular death or hospitalization for HF, myocardial infarction, stroke and CKD. RESULTS: Overall, SGLT2is were associated with reductions in all-cause mortality, cardiovascular mortality, hospitalization for HF and hospitalization for CKD compared with DPP4is. In patients with no CVRD history, SGLT2is were associated with reductions in all-cause mortality (HR 0.71, 95% CI 0.57-0.88; P = .002), hospitalization for HF (HR 0.76, 95% CI 0.59-0.98; P = .035) and hospitalization for CKD (HR 0.75, 95% CI 0.63-0.88; P < .001). In patients with established cardiovascular disease (CVD) or at high risk, SGLT2is were associated with reductions in all-cause mortality (HR 0.69, 95% CI 0.59-0.82; P < .001), cardiovascular mortality (HR 0.76, 95% CI 0.62-0.95; P = .014), hospitalization for HF (HR 0.73, 95% CI 0.63-0.85; P < .001), hospitalization for stroke (HR 0.75, 95% CI 0.59-0.94; P = .013) and hospitalization for CKD (HR 0.49, 95% CI 0.43-0.54; P < .001). CONCLUSION: There was consistency across subgroups and sensitivity analyses. SGLT2is were associated with a reduced risk of all-cause mortality and hospitalization for HF and CKD compared with DPP4-is, highlighting the need to introduce SGLT2is early in the management of patients with T2D.


Asunto(s)
Enfermedades Cardiovasculares , Diabetes Mellitus Tipo 2 , Inhibidores de la Dipeptidil-Peptidasa IV , Insuficiencia Cardíaca , Infarto del Miocardio , Insuficiencia Renal Crónica , Inhibidores del Cotransportador de Sodio-Glucosa 2 , Simportadores , Enfermedades Cardiovasculares/epidemiología , Enfermedades Cardiovasculares/prevención & control , Diabetes Mellitus Tipo 2/complicaciones , Diabetes Mellitus Tipo 2/tratamiento farmacológico , Inhibidores de la Dipeptidil-Peptidasa IV/uso terapéutico , Dipeptidil-Peptidasas y Tripeptidil-Peptidasas , Glucosa , Insuficiencia Cardíaca/epidemiología , Hospitalización , Humanos , Atención Primaria de Salud , Insuficiencia Renal Crónica/complicaciones , Insuficiencia Renal Crónica/epidemiología , Estudios Retrospectivos , Sodio , Inhibidores del Cotransportador de Sodio-Glucosa 2/uso terapéutico , Reino Unido/epidemiología
4.
Nanoscale ; 10(17): 7957-7965, 2018 May 03.
Artículo en Inglés | MEDLINE | ID: mdl-29682653

RESUMEN

Artificial atomic systems in solids are becoming increasingly important building blocks in quantum information processing and scalable quantum nanophotonic networks. Amongst numerous candidates, 2D hexagonal boron nitride has recently emerged as a promising platform hosting single photon emitters. Here, we report a number of robust plasma and thermal annealing methods for fabrication of emitters in tape-exfoliated hexagonal boron nitride (hBN) crystals. A two-step process comprising Ar plasma etching and subsequent annealing in Ar is highly robust, and yields an eight-fold increase in the concentration of emitters in hBN. The initial plasma-etching step generates emitters that suffer from blinking and bleaching, whereas the two-step process yields emitters that are photostable at room temperature with emission wavelengths greater than ∼700 nm. Density functional theory modeling suggests that the emitters might be associated with defect complexes that contain oxygen. This is further confirmed by generating the emitters via annealing hBN in air. Our findings advance the present understanding of the structure of quantum emitters in hBN and enhance the nanofabrication toolkit needed to realize integrated quantum nanophotonic circuits.

6.
Opt Express ; 22(3): 3186-98, 2014 Feb 10.
Artículo en Inglés | MEDLINE | ID: mdl-24663610

RESUMEN

We investigate the tunability and strength of the localized surface plasmons of binary metal-in-metal core-shells. Ellipsoids are used as an analytical model to show how the fill factor continuously tunes a hybridized mode between those of the constituents, suggesting the use of metal combinations with widely differing plasma frequencies for broad tunability. A quasistatic eigenmode method is used separate geometric and material parameters to facilitate prediction of hybridized dipole modes in arbitrary shapes. A modified ellipsoid model is found to adequately describe the symmetric dipole-dipole resonance of well-rounded cuboids.

7.
Sci Rep ; 2: 924, 2012.
Artículo en Inglés | MEDLINE | ID: mdl-23226591

RESUMEN

Faceted crystals with exposed highly reactive planes have attracted intensive investigations for applications such as hydrogen production, enhanced catalytic activity, and electrochemical energy storage and conversion. Herein, we report the synthesis of mesoporous NiO crystals with dominantly exposed {110} reactive facets by the thermal conversion of hexagonal Ni(OH)(2) nanoplatelets. When applied as anode materials in lithium-ion batteries, mesoporous NiO crystals exhibit a high reversible lithium storage capacity of 700 mAh g(-1) at 1 C rate in 100 cycles and an excellent cyclability. In particular, the dominantly exposed {110} reactive facets and mesoporous nanostructure of NiO crystals lead to ultrafast lithium storage, which mimics the high power delivery of supercapacitors.

8.
Phys Rev Lett ; 109(14): 146103, 2012 Oct 05.
Artículo en Inglés | MEDLINE | ID: mdl-23083260

RESUMEN

Models of adsorbate dissociation by energetic electrons are generalized to account for activated sticking and chemisorption, and used to simulate the rate kinetics of electron beam induced chemical vapor deposition (EBID). The model predicts a novel temperature dependence caused by thermal transitions from physisorbed to chemisorbed states that govern adsorbate coverage and EBID rates at elevated temperatures. We verify these results by experiments that also show how EBID can be used to deposit high purity materials and characterize the rates and energy barriers that govern adsorption.

9.
J Sports Sci ; 24(11): 1223-33, 2006 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-17176526

RESUMEN

We tested some of the key predictions of processing efficiency theory using a simulated rally driving task. Two groups of participants were classified as either dispositionally high or low anxious based on trait anxiety scores and trained on a simulated driving task. Participants then raced individually on two similar courses under counterbalanced experimental conditions designed to manipulate the level of anxiety experienced. The effort exerted on the driving tasks was assessed though self-report (RSME), psychophysiological measures (pupil dilation) and visual gaze data. Efficiency was measured in terms of efficiency of visual processing (search rate) and driving control (variability of wheel and accelerator pedal) indices. Driving performance was measured as the time taken to complete the course. As predicted, increased anxiety had a negative effect on processing efficiency as indexed by the self-report, pupillary response and variability of gaze data. Predicted differences due to dispositional levels of anxiety were also found in the driving control and effort data. Although both groups of drivers performed worse under the threatening condition, the performance of the high trait anxious individuals was affected to a greater extent by the anxiety manipulation than the performance of the low trait anxious drivers. The findings suggest that processing efficiency theory holds promise as a theoretical framework for examining the relationship between anxiety and performance in sport.


Asunto(s)
Ansiedad/psicología , Conducción de Automóvil/psicología , Conducta Competitiva/fisiología , Eficiencia/fisiología , Desempeño Psicomotor , Adulto , Análisis de Varianza , Movimientos Oculares/fisiología , Humanos , Masculino , Modelos Teóricos , Inventario de Personalidad , Reflejo Pupilar/fisiología
10.
J Clin Gastroenterol ; 38(8): 658-63, 2004 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-15319647

RESUMEN

GOALS: This study characterizes cardiovascular autonomic function in women with irritable bowel syndrome (IBS), using standardized techniques. BACKGROUND: Autonomic dysfunction is believed to contribute to abnormal gastrointestinal motility and visceral hypersensitivity in IBS. There is mounting evidence of generalized impairment of autonomic activity in patients with IBS. STUDY: Thirty women aged 39 years (95% C.I. 25-53 years) diagnosed with IBS, and 30 age-matched healthy women were studied. The ratio of low frequency to high frequency heart rate variability domains (LF:HF ratio) was used to represent cardiac sympathovagal activity, and orthostatic testing and sustained isometric handgrip exercise were used as sympathetic stimuli. Parasympathetic activity was represented by the expiratory to inspiratory R-R interval (E:I) ratio during deep breathing at 6 minutes. RESULTS: LF:HF responses to handgrip exercise (316%, C.I. 134% to 498% vs. 107%, C.I. 15% to 153%; P < 0.05) and orthostatic testing (648%, C.I. 520% to 904% vs. 330%, C.I. 140% to 520%; P < 0.05) were higher in IBS patients than controls, and the E:I ratio was significantly lower (1.47, C.I. 1.33-1.61 vs. 1.20, C.I. 1.14-1.26; P < 0.01). CONCLUSIONS: Autonomic cardiovascular function is impaired in IBS, manifest as attenuated cardio-vagal tone, and relative sympathetic excess during stimulated conditions.


Asunto(s)
Sistema Nervioso Autónomo/fisiopatología , Sistema Cardiovascular/fisiopatología , Síndrome del Colon Irritable/fisiopatología , Adolescente , Adulto , Femenino , Humanos , Persona de Mediana Edad
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