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1.
J Am Chem Soc ; 142(38): 16429-16436, 2020 09 23.
Artigo em Inglês | MEDLINE | ID: mdl-32862644

RESUMO

Nonoxidative dehydrogenation is promising for production of light olefins from shale gas, but current technology relies on precious Pt or toxic Cr catalysts and suffers from thermodynamically oriented coke formation. To solve these issues, the earth-abundant iron catalyst is employed, where Fe species are effectively modulated by siliceous zeolite, which is realized by the synthesis of Fe-containing MFI siliceous zeolite in the presence of ethylenediaminetetraacetic sodium (FeS-1-EDTA). Catalytic tests in ethane dehydrogenation show that this catalyst has a superior coke resistance in a 200 h run without any deactivation with extremely high activity and selectivity (e.g., 26.3% conversion and over 97.5% selectivity to ethene in at 873 K, close to the thermodynamic equilibrium limitation). Multiple characterizations demonstrate that the catalyst has uniformly and stably isolated Fe sites, which improves ethane dehydrogenation to facilitate the fast desorption of hydrogen and olefin products in the zeolite micropores and hinders the coke formation, as also identified by density functional calculations.

2.
Geriatr Orthop Surg Rehabil ; 11: 2151459320901997, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32064140

RESUMO

INTRODUCTION: Comanagement of hip fractures is thought to optimize outcomes for these high-risk patients, but this practice is not universal. We aimed to determine whether comanagement of patients with hip fracture affects 30-day outcomes. METHODS: The American College of Surgeons National Surgical Quality Improvement Program database was queried for all hip fractures between January 2015 and January 2017, totaling 15 461 patients (144 hospitals). Patients were divided into 3 cohorts: 11 233 comanaged throughout stay (CM), 2537 partially comanaged during stay (PCM), or 1691 not comanaged (NCM), by orthopedic surgeons with medicine physicians or geriatricians. Data collected included demographics, hip fracture type, postoperative outcomes, and length of stay (LOS). Logistic regression and linear regression analyses were performed. RESULTS: Both CM and PCM patients were older, with more dementia, poorer mobility, and more comorbidities than NCM patients. Mortality rates were 4.55%, 0.81%, and 0.33% for CM, PCM, and NCM, respectively, and risk-adjusted odds ratios (ORs) were 1.63 (95% confidence interval = 1.22-2.23) and 1.22 (0.87-1.74) for CM and PCM, respectively, compared to NCM. Morbidity rates were 11.06%, 15.45%, and 7.63% for CM, PCM, and NCM, respectively, and ORs were 1.74 (1.41-2.16) and 1.94 (1.57-2.41) for CM and PCM, respectively, compared to NCM. Risk-adjusted mean square LOS was 6.38, 8.80, and 7.23 for CM, PCM, and NC, respectively (P < .01). CONCLUSIONS: Comanaged patients with hip fracture had poorer cognition, function, and general health, with the shortest LOS. Surprisingly, NCM was associated with reduced morbidity and mortality, which may relate to them being the healthiest patients. Overall, our findings still support orthogeriatric comanagement in this high-risk group to maximize outcomes.

3.
High Alt Med Biol ; 20(4): 421-426, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31618098

RESUMO

Introduction: The relationship between altitude during treatment and common postoperative infections remains to be established. Based on the inverse relationship between oxygen partial pressure and altitude, we hypothesized that hospital elevation would correlate positively with postoperative infectious complication rates, including surgical site infection (SSI), urinary tract infection (UTI), and pneumonia. Methods: We used an event-enriched population of general, urologic, vascular, plastic-reconstructive, orthopedic, and thoracic patients within the 2016 ACS National Surgical Quality Improvement Program (NSQIP) dataset who underwent procedures with high risk of infectious complications. This yielded 82,172, 175,409, and 88,856 patients from 571, 577, and 570 hospitals for the study of 30-day postoperative SSI, UTI, and pneumonia outcomes respectively. Hospital altitudes were determined using Google Maps. Data were analyzed using univariate (altitude) and multivariate logistic regression, with altitude forced into the model, and forward-selection of NSQIP variables, with adjustment for clustering by hospital. Results: When compared in 1000-foot increments above sea level, hospital altitude had no significant effect on SSI or UTI (odds ratio [OR] = 1.0, p > 0.05). The risk of postoperative pneumonia decreased with increased altitude (OR = 0.93, 95% confidence interval: 0.87-0.99, p = 0.03). Conclusions: Patients and providers should be reassured that there is no increased risk of SSI or UTI at higher altitudes. The decreased risk of postoperative pneumonia was surprising and there exist potential explanations warranting future investigation.


Assuntos
Pneumonia Associada a Assistência à Saúde/etiologia , Hospitais/estatística & dados numéricos , Complicações Pós-Operatórias/etiologia , Infecção da Ferida Cirúrgica/etiologia , Infecções Urinárias/etiologia , Idoso , Altitude , Bases de Dados Factuais , Exposição Ambiental/efeitos adversos , Exposição Ambiental/análise , Feminino , Geografia , Pneumonia Associada a Assistência à Saúde/epidemiologia , Humanos , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Complicações Pós-Operatórias/epidemiologia , Fatores de Risco , Infecção da Ferida Cirúrgica/epidemiologia , Estados Unidos/epidemiologia , Infecções Urinárias/epidemiologia
4.
ACS Appl Mater Interfaces ; 10(39): 33214-33220, 2018 Oct 03.
Artigo em Inglês | MEDLINE | ID: mdl-30203642

RESUMO

Modern methodologies for synthesizing zeolites typically involve the employment of costly organic structure-directing agents. Herein, we report the design synthesis of aluminosilicate zeolite with ITE structure using an inexpensive nickel-amine complex (nickel-pentaethylenexamine) as a novel structure-directing agent. Characterizations including X-ray diffraction, scanning electron microscopy, N2 sorption isotherms, and 27Al magic-angle spinning NMR techniques show that the ITE zeolite has high crystallinity, perfect crystals, large surface area, and abundant aluminum species in the framework. More importantly, catalytic tests on the hydrogenation of CO2 into methane show that the Ni-ITE zeolite exhibits better catalytic performance than aluminosilicate-supported and silica-supported nickel catalysts. Obviously, the use of nickel-amine complex offers an alternative and facile way to synthesize aluminosilicate zeolites.

5.
J Am Coll Surg ; 217(2): 336-46.e1, 2013 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-23628227

RESUMO

The American College of Surgeons National Surgical Quality Improvement Program (ACS NSQIP) collects detailed clinical data from participating hospitals using standardized data definitions, analyzes these data, and provides participating hospitals with reports that permit risk-adjusted comparisons with a surgical quality standard. Since its inception, the ACS NSQIP has worked to refine surgical outcomes measurements and enhance statistical methods to improve the reliability and validity of this hospital profiling. From an original focus on controlling for between-hospital differences in patient risk factors with logistic regression, ACS NSQIP has added a variable to better adjust for the complexity and risk profile of surgical procedures (procedure mix adjustment) and stabilized estimates derived from small samples by using a hierarchical model with shrinkage adjustment. New models have been developed focusing on specific surgical procedures (eg, "Procedure Targeted" models), which provide opportunities to incorporate indication and other procedure-specific variables and outcomes to improve risk adjustment. In addition, comparative benchmark reports given to participating hospitals have been expanded considerably to allow more detailed evaluations of performance. Finally, procedures have been developed to estimate surgical risk for individual patients. This article describes the development of, and justification for, these new statistical methods and reporting strategies in ACS NSQIP.


Assuntos
Benchmarking/estatística & dados numéricos , Hospitais/normas , Modelos Estatísticos , Melhoria de Qualidade/estatística & dados numéricos , Risco Ajustado/métodos , Procedimentos Cirúrgicos Operatórios/normas , Humanos , Modelos Logísticos , Risco Ajustado/tendências , Estados Unidos
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