Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 12 de 12
Filtrar
1.
J Endovasc Ther ; 28(4): 567-574, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-33970044

RESUMO

PURPOSE: Percutaneous lower extremity revascularization is being performed via upper extremity, pedal, or popliteal access with increasing frequency. This study aimed to compare periprocedural outcomes of popliteal (POA) and upper extremity (UEA) access for the treatment of isolated superficial femoral artery (SFA) occlusive disease. MATERIALS AND METHODS: A retrospective cohort study compared the outcomes of patients undergoing primary percutaneous intervention of SFA occlusive disease with POA or UEA using the Vascular Quality Initiative database from December 2010 to June 2019. Our primary endpoint was technical success. Secondary endpoints included factors associated with perioperative complications. RESULTS: A total of 349 patients underwent isolated SFA intervention through the popliteal, radial, or brachial artery. UEA was performed in 188 (53.9%) patients and POA in 161 (46.1%). Technical success with TASC A lesions was 95.8% and with TASC D lesions, 65.0%. POA had a higher proportion of TASC D lesions (24.8% vs 10.6%, p<0.001), and larger (≥7 Fr) sheath size (14.3% vs 2.7%, p<0.001). UEA had a higher proportion of no calcification (27.1% vs 11.2%, p<0.001), and smaller (4-5 Fr) sheath size (46.8% vs 34.8%, p=0.023). There was no difference in technical success between UEA and POA (88.8% vs 84.5%, p=0.230), which was also seen on multivariable analysis (p=0.985). Univariate analysis revealed technical failure was associated with TASC D lesions (45.7% vs 12.9%, p<0.001) and the presence of severe calcifications (39.1% vs 17.5%, p=0.002). Multivariable analysis confirmed technical failure was associated with degree of calcification (OR, 2.4; 95% CI, 1.18 to 4.89; p=0.016) and TASC D lesions (OR, 5.01; 95% CI, 2.45 to 10.24; p<0.001). Postoperative complications were associated with UEA on univariate (p=0.041) and multivariate analysis (OR, 2.08; 95% CI, 0.80 to 5.37; p=0.016). Access site complications were also associated with UEA compared to POA (4.3% vs 0.0%, p=0.027). CONCLUSIONS: There is no difference in technical success between UEA and POA when treating isolated SFA occlusive disease, and UEA is associated with a higher complication rate. Technical success is dependent on calcification and TASC II classification. Based on similar technical success rates and low complication rates, POA should be considered as a viable alternative to UEA when planning endovascular interventions.


Assuntos
Arteriopatias Oclusivas , Artéria Femoral , Arteriopatias Oclusivas/diagnóstico por imagem , Arteriopatias Oclusivas/cirurgia , Artéria Femoral/diagnóstico por imagem , Artéria Femoral/cirurgia , Humanos , Artéria Poplítea/diagnóstico por imagem , Artéria Poplítea/cirurgia , Estudos Retrospectivos , Stents , Resultado do Tratamento , Extremidade Superior , Grau de Desobstrução Vascular
2.
Nat Commun ; 14(1): 64, 2023 Jan 04.
Artigo em Inglês | MEDLINE | ID: mdl-36599865

RESUMO

Load bearing/energy storage integrated devices (LEIDs) allow using structural parts to store energy, and thus become a promising solution to boost the overall energy density of mobile energy storage systems, such as electric cars and drones. Herein, with a new high-strength solid electrolyte, we prepare a practical high-performance load-bearing/energy storage integrated electrochemical capacitors with excellent mechanical strength (flexural modulus: 18.1 GPa, flexural strength: 160.0 MPa) and high energy storage ability (specific capacitance: 32.4 mF cm-2, energy density: 0.13 Wh m-2, maximum power density: 1.3 W m-2). We design and compare two basic types of multilayered structures for LEID, which significantly enhance the practical bearing ability and working flexibility of the device. Besides, we also demonstrate the excellent processability of the LEID, by forming them into curved shapes, and secondarily machining and assembling them into complex structures without affecting their energy storage ability.

3.
RSC Adv ; 10(37): 22019-22026, 2020 Jun 08.
Artigo em Inglês | MEDLINE | ID: mdl-35516650

RESUMO

Polyaniline gels with a three-dimensional network structure are attractive for their broad application prospects in flexible and stretchable electric devices. In this paper, we develop a facile solution assembly method to prepare an elastic polyaniline/poly(vinyl alcohol) composite organogel and a hydrogel. The polyaniline and poly(vinyl alcohol) chains gelate from the homogeneous mixed solution in N-methyl-2-pyrrolidone via crystallization of poly(vinyl alcohol), producing a uniform organogel with hydrogen bonds between two polymers, and the organogel can be further converted into a hydrogel by solvent exchange. The composite gels exhibit excellent mechanical properties, which make them one of the best materials for additive manufacture, such as molding and 3D printing. This study develops an efficient method to fabricate polyaniline gels with good processability and multifunctions.

4.
JCO Clin Cancer Inform ; 4: 1059-1071, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-33253013

RESUMO

PURPOSE: While the immediate care and access disruptions associated with the COVID-19 pandemic have received growing attention in certain areas, the full range of gaps in cancer screenings and treatment is not yet well understood or well documented throughout the country comprehensively. METHODS: This study used a large medical claims clearinghouse database representing 5%-7% of the Medicare fee-for-service population to characterize changes in the utilization of cancer care services and gain insight into the impact of COVID-19 on the US cancer population, including identification of new patients, gaps in access to care, and disruption of treatment journeys. RESULTS: In March-July 2020, in comparison with the baseline period of March-July 2019, there is a substantial decrease in cancer screenings, visits, therapy, and surgeries, with variation by cancer type and site of service. At the peak of the pandemic in April, screenings for breast, colon, prostate, and lung cancers were lower by 85%, 75%, 74%, and 56%, respectively. Significant utilization reductions were observed in April for hospital outpatient evaluation and management (E&M) visits (-74%), new patient E&M visits (-70%), and established patient E&M visits (-60%). A decrease in billing frequency was observed for the top physician-administered oncology products, dropping in both April (-26%) and July (-31%). Mastectomies were reduced consistently in April through July, with colectomies similarly reduced in April and May and prostatectomies dipping in April and July. CONCLUSION: The current impact of the COVID-19 pandemic on cancer care in the United States has resulted in decreases and delays in identifying new cancers and delivery of treatment. These problems, if unmitigated, will increase cancer morbidity and mortality for years to come.


Assuntos
COVID-19/epidemiologia , Detecção Precoce de Câncer/tendências , Oncologia/tendências , Medicare , Neoplasias/diagnóstico , Pandemias , Idoso , Feminino , Humanos , Masculino , Neoplasias/terapia , Estados Unidos/epidemiologia
7.
ACS Nano ; 12(6): 5888-5894, 2018 Jun 26.
Artigo em Inglês | MEDLINE | ID: mdl-29750500

RESUMO

Although challenging, fabrication of porous conducting polymeric materials with excellent electronic properties is crucial for many applications. We developed a fast in situ polymerization approach to pure polyaniline (PANI) hydrogels, with vanadium pentoxide hydrate nanowires as both the oxidant and sacrifice template. A network comprised of ultrathin PANI nanofibers was generated during the in situ polymerization, and the large aspect ratio of these PANI nanofibers allowed the formation of hydrogels at a low solid content of 1.03 wt %. Owing to the ultrathin fibril structure, PANI hydrogels functioning as a supercapacitor electrode display a high specific capacitance of 636 F g-1, a rate capability, and good cycling stability (∼83% capacitance retention after 10,000 cycles). This method was also extended to the preparation of polypyrrole and poly(3,4-ethylenedioxythiophene) hydrogels. This template polymerization method represents a rational strategy for design of conducing polymer networks, which can be readily integrated in high-performance devices or a further platform for functional composites.

8.
ChemSusChem ; 10(15): 3098-3104, 2017 08 10.
Artigo em Inglês | MEDLINE | ID: mdl-28661581

RESUMO

Although organic small molecule spiro-OMeTAD is widely used as a hole-transport material in perovskite solar cells, its limited electric conductivity poses a bottleneck in the efficiency improvement of perovskite solar cells. Here, a low-cost and easy-fabrication technique is developed to enhance the conductivity and hole-extraction ability of spiro-OMeTAD by doping it with commercially available benzoyl peroxide (BPO). The experimental results show that the conductivity increases several orders of magnitude, from 6.2×10-6  S cm-1 for the pristine spiro-OMeTAD to 1.1×10-3  S cm-1 at 5 % BPO doping and to 2.4×10-2  S cm-1 at 15 % BPO doping, which considerably outperform the conductivity of 4.62×10-4  S cm-1 for the currently used oxygen-doped spiro-OMeTAD. The fluorescence spectra suggest that the BPO-doped spiro-OMeTAD-OMeTAD layer is able to efficiently extract holes from CH3 NH3 PbI3 and thus greatly enhances the charge transfer. The BPO-doped spiro-OMeTAD is used in the fabrication of perovskite solar cells, which exhibit enhancement in the power conversion efficiency.


Assuntos
Peróxido de Benzoíla/química , Compostos de Cálcio/química , Fontes de Energia Elétrica , Fluorenos/química , Óxidos/química , Energia Solar , Compostos de Espiro/química , Titânio/química , Eletroquímica
9.
ACS Appl Mater Interfaces ; 8(7): 4724-9, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26830192

RESUMO

Flexible solid-state supercapacitors attract more and more attention as the power supply for wearable electronics. To fabricate such devices, the flexible and economical current collectors are needed. In this paper, we report the stainless steel fabrics as the current collector for high-performance graphene-based supercapacitors. The stainless steel fabrics have superior properties compared with the widely used flexible current collectors. The flexible supercapacitors show large specific capacitance of 180.4 mF/cm(2), and capacitance retention of 96.8% after 7500 charge-discharge cycles. Furthermore, 96.4% of the capacitance is retained after 800 repeating stretching-bending cycles. The high performance is related to the excellent conductivity, good mechanical flexibility, and high electrochemical stability of the stainless steel fabrics. The achievement of such high-performance and flexible supercapacitor can open up exciting opportunities for wearable electronics and energy storage applications.

10.
Adv Mater ; 28(8): 1703-8, 2016 Feb 24.
Artigo em Inglês | MEDLINE | ID: mdl-26678843

RESUMO

2D ultrathin aluminum oxide (2D-Al2O3) nanosheets are prepared by duplicating graphene oxide. An amorphous precursor of the hydroxide of aluminum is first deposited onto graphene oxide sheets, which are then converted into 2D-Al2 O3 nanosheets by calcination, while the graphene oxide is removed. The 2D-Al2O3 nanosheets have a large specific surface area and a superior adsorption capacity to fluoride ions.

11.
Adv Mater ; 28(46): 10211-10216, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-27723115

RESUMO

Polyaniline/graphene hydrogel composites with a macroscopically phase-separated structure are prepared. The composites show high specific capacitance and excellent rate performance. Further investigation demonstrates that polyaniline inside the graphene hydrogel has low rate performance, thus a phase-separated structure, in which polyaniline is mainly outside the graphene hydrogel matrix, can enhance the rate performance of the composites.

SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA