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1.
J Chem Inf Model ; 2021 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-34048230

RESUMO

In chemical kinetics research, kinetic models containing hundreds of species and tens of thousands of elementary reactions are commonly used to understand and predict the behavior of reactive chemical systems. Reaction Mechanism Generator (RMG) is a software suite developed to automatically generate such models by incorporating and extrapolating from a database of known thermochemical and kinetic parameters. Here, we present the recent version 3 release of RMG and highlight improvements since the previously published description of RMG v1.0. Most notably, RMG can now generate heterogeneous catalysis models in addition to the previously available gas- and liquid-phase capabilities. For model analysis, new methods for local and global uncertainty analysis have been implemented to supplement first-order sensitivity analysis. The RMG database of thermochemical and kinetic parameters has been significantly expanded to cover more types of chemistry. The present release includes parallelization for faster model generation and a new molecule isomorphism approach to improve computational performance. RMG has also been updated to use Python 3, ensuring compatibility with the latest cheminformatics and machine learning packages. Overall, RMG v3.0 includes many changes which improve the accuracy of the generated chemical mechanisms and allow for exploration of a wider range of chemical systems.

2.
Gigascience ; 10(3)2021 03 12.
Artigo em Inglês | MEDLINE | ID: mdl-33710327

RESUMO

BACKGROUND: Digitaria exilis, white fonio, is a minor but vital crop of West Africa that is valued for its resilience in hot, dry, and low-fertility environments and for the exceptional quality of its grain for human nutrition. Its success is hindered, however, by a low degree of plant breeding and improvement. FINDINGS: We sequenced the fonio genome with long-read SMRT-cell technology, yielding a ∼761 Mb assembly in 3,329 contigs (N50, 1.73 Mb; L50, 126). The assembly approaches a high level of completion, with a BUSCO score of >99%. The fonio genome was found to be a tetraploid, with most of the genome retained as homoeologous duplications that differ overall by ∼4.3%, neglecting indels. The 2 genomes within fonio were found to have begun their independent divergence ∼3.1 million years ago. The repeat content (>49%) is fairly standard for a grass genome of this size, but the ratio of Gypsy to Copia long terminal repeat retrotransposons (∼6.7) was found to be exceptionally high. Several genes related to future improvement of the crop were identified including shattering, plant height, and grain size. Analysis of fonio population genetics, primarily in Mali, indicated that the crop has extensive genetic diversity that is largely partitioned across a north-south gradient coinciding with the Sahel and Sudan grassland domains. CONCLUSIONS: We provide a high-quality assembly, annotation, and diversity analysis for a vital African crop. The availability of this information should empower future research into further domestication and improvement of fonio.

3.
J Phys Chem A ; 125(4): 1036-1049, 2021 Feb 04.
Artigo em Inglês | MEDLINE | ID: mdl-33475373

RESUMO

Interfacial regions are unique chemical reaction environments that can promote chemistry not found elsewhere. The air-water interface is ubiquitous in the natural environment in the form of ocean surfaces and aqueous atmospheric aerosols. Here we investigate the chemistry and photochemistry of pyruvic acid (PA), a common environmental species, at the air-water interface and compare it to its aqueous bulk chemistry using two different experimental setups: (1) a Langmuir-Blodgett trough, which models natural water surfaces and provides a direct comparison between the two reaction environments, and (2) an atmospheric simulation chamber (CESAM) to monitor the chemical processing of nebulized aqueous PA droplets. The results show that surface chemistry leads to substantial oligomer formation. The sequence begins with the condensation of lactic acid (LA), formed at the surface, with itself and with pyruvic acid, and LA + LA - H2O and LA + PA - H2O are prominent among the products in addition to a series of higher-molecular-weight oligomers of mixed units of PA and LA. In addition, we see zymonic acid at the surface. Actinic radiation enhances the production of the oligomers and produces additional surface-active molecules known from the established aqueous photochemical mechanisms. The presence and formation of complex organic molecules at the air-water interface from a simple precursor like PA in the natural environment is relevant to contemporary atmospheric science and is important in the context of prebiotic chemistry, where abiotic production of complex molecules is necessary for abiogenesis.

4.
J. vasc. interv. radiol ; 31(10): 1529-1544, Oct. 2020.
Artigo em Inglês | BIGG - guias GRADE | ID: biblio-1128259

RESUMO

To provide evidence-based recommendations on the use of inferior vena cava (IVC) filters in the treatment of patients with or at substantial risk of venous thromboembolic disease. A multidisciplinary expert panel developed key questions to address in the guideline, and a systematic review of the literature was conducted. Evidence was graded based on a standard methodology, which was used to inform the development of recommendations. The systematic review identified a total of 34 studies that provided the evidence base for the guideline. The expert panel agreed on 18 recommendations. Although the evidence on the use of IVC filters in patients with or at risk of venous thromboembolic disease varies in strength and quality, the panel provides recommendations for the use of IVC filters in a variety of clinical scenarios. Additional research is needed to optimize care for this patient population.


Assuntos
Humanos , Trombose Venosa/diagnóstico , Trombose Venosa/prevenção & controle , Trombose Venosa/terapia , Filtros de Veia Cava , Política Informada por Evidências
5.
J Vasc Interv Radiol ; 31(10): 1529-1544, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32919823

RESUMO

PURPOSE: To provide evidence-based recommendations on the use of inferior vena cava (IVC) filters in the treatment of patients with or at substantial risk of venous thromboembolic disease. MATERIALS AND METHODS: A multidisciplinary expert panel developed key questions to address in the guideline, and a systematic review of the literature was conducted. Evidence was graded based on a standard methodology, which was used to inform the development of recommendations. RESULTS: The systematic review identified a total of 34 studies that provided the evidence base for the guideline. The expert panel agreed on 18 recommendations. CONCLUSIONS: Although the evidence on the use of IVC filters in patients with or at risk of venous thromboembolic disease varies in strength and quality, the panel provides recommendations for the use of IVC filters in a variety of clinical scenarios. Additional research is needed to optimize care for this patient population.


Assuntos
Implantação de Prótese/instrumentação , Implantação de Prótese/normas , Radiologia Intervencionista/normas , Filtros de Veia Cava/normas , Tromboembolia Venosa/terapia , Consenso , Humanos , Segurança do Paciente/normas , Desenho de Prótese , Implantação de Prótese/efeitos adversos , Fatores de Risco , Resultado do Tratamento , Tromboembolia Venosa/diagnóstico por imagem , Tromboembolia Venosa/etiologia
6.
Sci Rep ; 10(1): 12465, 2020 07 27.
Artigo em Inglês | MEDLINE | ID: mdl-32719313

RESUMO

Methane (CH4) is emitted from lakes by several processes: bubbles released from bottom sediments that reach the atmosphere (ebullition); spring release of CH4 trapped in bubbles in and under the ice during fall freeze (bubble release), and diffusion of CH4 from sediments to the surface. Each of these emission routes is highly variable over space and time, and episodic in the extreme, making reliable measurements difficult to carry out. However, lakes are receiving increasing interest for their important contribution to global CH4 emissions. Their area, distribution and emissions respond to interannual and longer-term climate fluctuations and close to half the world's lake area is in high northern latitudes that are experiencing rapidly-warming temperatures and lengthening thaw periods. We report on a new spatially-explicit data set of lakes > 50°N, classified with methane-relevant criteria. The seasonality of daily CH4 fluxes is driven with satellite observations of thaw timing and duration. We found that observed thaw seasons are 10-30% shorter than those assumed in previous studies. The area of lakes is 1,095 × 103 km2 and total CH4 emission is 13.8-17.7 Tg CH4 year-1: 11.2-14.4 Tg via diffusion and ebullition and 2.6-3.3 Tg from spring release of CH4 stored in bubbles in winter lake ice. This novel suite of data and methodologies provides a unique framework to model CH4 emission from lakes under current, past and future climates.

7.
Rapid Commun Mass Spectrom ; 34(20): e8858, 2020 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-32548934

RESUMO

The isotopic composition of nitrous oxide (N2 O) provides useful information for evaluating N2 O sources and budgets. Due to the co-occurrence of multiple N2 O transformation pathways, it is, however, challenging to use isotopic information to quantify the contribution of distinct processes across variable spatiotemporal scales. Here, we present an overview of recent progress in N2 O isotopic studies and provide suggestions for future research, mainly focusing on: analytical techniques; production and consumption processes; and interpretation and modelling approaches. Comparing isotope-ratio mass spectrometry (IRMS) with laser absorption spectroscopy (LAS), we conclude that IRMS is a precise technique for laboratory analysis of N2 O isotopes, while LAS is more suitable for in situ/inline studies and offers advantages for site-specific analyses. When reviewing the link between the N2 O isotopic composition and underlying mechanisms/processes, we find that, at the molecular scale, the specific enzymes and mechanisms involved determine isotopic fractionation effects. In contrast, at plot-to-global scales, mixing of N2 O derived from different processes and their isotopic variability must be considered. We also find that dual isotope plots are effective for semi-quantitative attribution of co-occurring N2 O production and reduction processes. More recently, process-based N2 O isotopic models have been developed for natural abundance and 15 N-tracing studies, and have been shown to be effective, particularly for data with adequate temporal resolution. Despite the significant progress made over the last decade, there is still great need and potential for future work, including development of analytical techniques, reference materials and inter-laboratory comparisons, further exploration of N2 O formation and destruction mechanisms, more observations across scales, and design and validation of interpretation and modelling approaches. Synthesizing all these efforts, we are confident that the N2 O isotope community will continue to advance our understanding of N2 O transformation processes in all spheres of the Earth, and in turn to gain improved constraints on regional and global budgets.

8.
Anesth Analg ; 131(1): 288-297, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32543805

RESUMO

BACKGROUND: The inhalation anesthetics are potent greenhouse gases. To reduce the global environmental impact of the health care sector, technologies are sought to limit the release of waste anesthetic gas into the atmosphere. METHODS: Using a photochemical exhaust gas destruction system, removal efficiencies for nitrous oxide, desflurane, and sevoflurane were measured at various inlet concentrations (25% and 50%; 1.5%, 3.0%, and 6.0%; and 0.5%, 1.0%, and 2.0%, respectively) with flow rates ranging from 0.25 to 2.0 L/min. To evaluate the economic competitiveness of the anesthetic waste gas destruction system, its price per ton of carbon dioxide equivalent was calculated and compared to other greenhouse gas abatement technologies and current market prices. RESULTS: All inhaled anesthetics evaluated demonstrate enhanced removal efficiencies with decreasing flow rates (P < .0001). Depending on the anesthetic and its concentration, the photochemical exhaust gas destruction system exhibits a constant first-order removal rate, k. However, there was not a simple relation between the removal rate k and the species concentration. The costs for removing a ton of carbon dioxide equivalents are <$0.005 for desflurane, <$0.114 for sevoflurane, and <$49 for nitrous oxide. CONCLUSIONS: Based on this prototype study, destroying sevoflurane and desflurane with this photochemical anesthetic waste gas destruction system design is efficient and cost-effective. This is likely also true for other halogenated inhalational anesthetics such as isoflurane. Due to differing chemistry of nitrous oxide, modifications of this prototype photochemical reactor system are necessary to improve its removal efficiency for this gas.


Assuntos
Anestésicos Inalatórios/efeitos adversos , Anestésicos Inalatórios/química , Gases de Efeito Estufa/efeitos adversos , Gases de Efeito Estufa/química , Resíduos Perigosos/efeitos adversos , Fotoquímica/métodos , Anestesia por Inalação/efeitos adversos , Anestésicos Inalatórios/análise , Gases de Efeito Estufa/análise , Resíduos Perigosos/análise , Humanos
9.
Phys Chem Chem Phys ; 22(20): 11678-11685, 2020 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-32406445

RESUMO

Aqueous nitrate is ubiquitous in the environment, found for example in stratospheric clouds, tropospheric particulate matter, rain and snow, fertilized fields, rivers and the ocean. Its photolysis is initiated by absorption into the strongly forbidden n →π* transition. Photolysis reactivates deposited nitrate, releasing nitrogen oxides, and UV light is commonly used to break down nitrate pollution. The transition is doubly forbidden unless its symmetry is broken, giving a powerful means of probing the interactions of nitrate with its environment and of using experiment to validate the results of theory. In this study we demonstrate the remarkably different effects of the addition of a series of mono- and di-valent metal chlorides on the nitrate UV transition. While they all shift the transition to shorter wavelengths, the shift changes significantly from one to another. For the monovalent series Li+, Na+, K+, the blue shift decreases down the column being strongest for Li+ and weakest for K+. For the divalent series Mg2+, Ca2+, Ba2+, the opposite effect is observed with the energy shift of Ba2+ being an order of magnitude larger than for Mg2+. The absorption intensity also changes; the addition of Na+ and K+ decrease intensity whereas Li+ increases intensity. For the divalent cations an increase is seen for all three members of the series Mg2+, Ca2+ and Ba2+. Paradoxically, the effect of addition of CaCl2 to the solution is to decrease the environmental photolysis rate of nitrate; despite the increase in intensity, Ca2+ blue shifts the peak position above the tropospheric photolysis threshold around 300 nm. Using computational chemistry we conclude that the effects are due to the microscopic interactions of the nitrate anion and not continuum effects. Two microscopic mechanisms are investigated in detail, the formation of a nitrate monohydrate cluster and a contact ion pair. The contact ion pair shows the potential for significant impact on the energy and intensity of the transition.

10.
Sci Total Environ ; 704: 135325, 2020 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-31839317

RESUMO

Biotrickling filters (BTFs) applied to hydrophobic volatile organic compounds (VOCs) suffer from limited mass transfer. Phase transfer kinetic and equilibrium effects limit the biodegradation of hydrophobic VOCs especially at high concentrations. This study evaluates two strategies for overcoming the problem. First, a natural process was used to enhance the aqueous availability of styrene, a hydrophobic VOC model, by inoculating the BTF with a mixture of biosurfactant-generating bacteria. This method achieved a maximum elimination capacity (ECmax) of 139 g m-3h-1 in the BTF at an empty bed residence time (EBRT) of 60s. The highest concentrations of the biosurfactants surfactin and rhamnolipid were 205 and 86 mg L-1, respectively, in this step. Sequencing 16S rRNA confirmed the presence of biosurfactant-producing bacteria capable of biodegrading styrene in the BTF including Bacillus sonorensis, Bacillus subtilis, Lysinibacillus sphaericus, Lysinibacillus fusiformis, Alcaligenes feacalis, Arthrobacter creatinolyticus, and Kocuria rosea. Second, the effect of adding H2O2 to the recycle liquid on the BTF performance was determined. The biodegradation and mineralization of styrene in the BTF operated at a loading rate of 266 g m-3h-1 and H2O2/styrene molar ratio of 0.05 with EBRT as short as 15 s were 94% and 53%, respectively, with the EC of 250 g m-3h-1. High concentrations of antioxidant enzymes (peroxidase and catalase: 56 and 7 U gbiomass-1, respectively) were produced and biosurfactant generation was increased in this step, contributing to enhanced styrene biodegradation and mineralization. The styrene biodegradation and mineralization values in the BTF in the last day operated under similar conditions but without H2O2 were 11.4% and 5.3%, respectively. The bacterial population had no considerable change in the BTF after adding H2O2. Accordingly, stimulating the BTF inoculated with biosurfactant-generating bacteria with H2O2 is a promising strategy for improving the biodegradation of hydrophobic VOCs.


Assuntos
Poluentes Atmosféricos/metabolismo , Biodegradação Ambiental , Estireno/metabolismo , Poluentes Atmosféricos/análise , Reatores Biológicos , Peróxido de Hidrogênio , Estireno/análise , Compostos Orgânicos Voláteis/análise , Compostos Orgânicos Voláteis/metabolismo
11.
J Vasc Interv Radiol ; 31(2): 221-230.e3, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31711748

RESUMO

PURPOSE: To report final 2-year outcomes with the Sentry bioconvertible inferior vena cava (IVC) filter in patients requiring temporary protection against pulmonary embolism (PE). MATERIALS AND METHODS: In a prospective multicenter trial, the Sentry filter was implanted in 129 patients with documented deep vein thrombosis (DVT) and/or PE (67.5%) or who were at temporary risk of developing DVT/PE (32.6%). Patients were monitored and bioconversion status ascertained by radiography, computed tomography (CT), and CT venography through 2 years. RESULTS: The composite primary 6-month endpoint of clinical success was achieved in 97.4% (111/114) of patients. The rate of new symptomatic PE was 0% (n = 126) through 1 year and 2.4% (n = 85) through the second year of follow-up, with 2 new nonfatal cases at 581 and 624 days that were adjudicated as not related to the procedure or device. Two patients (1.6%) developed symptomatic caval thrombosis during the first month and underwent successful interventions without recurrence. No other filter-related symptomatic complications occurred through 2 years. There was no filter tilting, migration, embolization, fracture, or caval perforation and no filter-related deaths through 2 years. Filter bioconversion was successful for 95.7% (110/115) of patients at 6 months, 96.4% (106/110) of patients at 12 months, and 96.5% (82/85) of patients at 24 months. Through 24 months of follow-up, there was no evidence of late-stage IVC obstruction or thrombosis after filter bioconversion or of thrombogenicity associated with retracted filter arms. CONCLUSIONS: The Sentry IVC filter provided safe and effective protection against PE, with a high rate of intended bioconversion and a low rate of device-related complications, through 2 years of follow-up.


Assuntos
Implantação de Prótese/instrumentação , Embolia Pulmonar/prevenção & controle , Filtros de Veia Cava , Veia Cava Inferior , Trombose Venosa/prevenção & controle , Adulto , Idoso , Idoso de 80 Anos ou mais , Bélgica , Chile , Angiografia por Tomografia Computadorizada , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Flebografia , Desenho de Prótese , Implantação de Prótese/efeitos adversos , Embolia Pulmonar/diagnóstico por imagem , Fatores de Risco , Fatores de Tempo , Resultado do Tratamento , Estados Unidos , Veia Cava Inferior/diagnóstico por imagem , Trombose Venosa/diagnóstico por imagem , Adulto Jovem
12.
J Gastrointest Surg ; 24(10): 2228-2232, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31485902

RESUMO

PURPOSE: Transjugular intrahepatic portosystemic shunt (TIPS) creation is most commonly performed for patients with refractory ascites or variceal hemorrhage. While TIPS have also been created prior to planned abdominal operation to decrease morbidity related to portal hypertension, there are limited data supporting its effectiveness in that indication. The goal of this study was to determine if preoperative TIPS creation allows for successful abdominal operation with limited morbidity. METHODS: A retrospective review of records of 22 consecutive patients who underwent TIPS creation for the specific indication of improving surgical candidacy, between 2011 and 2016, was performed. Clinical and serologic data were obtained for 21 patients (one patient was excluded since she was completely lost to follow-up after TIPS creation). The primary endpoint was whether patients underwent planned abdominal operation following TIPS. Operative outcomes and reasons that patients failed to undergo planned operation were examined as secondary endpoints. The mean age was 56.4 ± 8.8 years and the mean Child-Pugh and Model for End-Stage Liver Disease (MELD) scores were 7.2 ± 1.5 and 11.9 ± 4.3, respectively. RESULTS: TIPS creation was performed in all 21 patients with a 30-day mortality rate of 9.5%. Eleven patients (52.4%) subsequently underwent abdominal operation after which the 30-day postoperative mortality rate was 0%. One patient (9.1%) had major perioperative morbidity related to portal hypertension and presented with surgical wound dehiscence and infection requiring drain placement and antibiotic therapy. CONCLUSIONS: In this population, TIPS allowed successful abdominal operation in the majority of patients, with 30-day TIPS mortality of 9.5%, no perioperative mortality, and 9.1% major postoperative morbidity attributable to portal hypertension.

13.
Br J Math Stat Psychol ; 73(3): 397-419, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31418458

RESUMO

According to Wollack and Schoenig (2018, The Sage encyclopedia of educational research, measurement, and evaluation. Thousand Oaks, CA: Sage, 260), benefiting from item preknowledge is one of the three broad types of test fraud that occur in educational assessments. We use tools from constrained statistical inference to suggest a new statistic that is based on item scores and response times and can be used to detect examinees who may have benefited from item preknowledge for the case when the set of compromised items is known. The asymptotic distribution of the new statistic under no preknowledge is proved to be a simple mixture of two χ2 distributions. We perform a detailed simulation study to show that the Type I error rate of the new statistic is very close to the nominal level and that the power of the new statistic is satisfactory in comparison to that of the existing statistics for detecting item preknowledge based on both item scores and response times. We also include a real data example to demonstrate the usefulness of the suggested statistic.

14.
J Vasc Surg Venous Lymphat Disord ; 8(2): 187-194.e1, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-31636051

RESUMO

BACKGROUND: Death from venous thromboembolism remains a significant cause of death worldwide. Although anticoagulation is the cornerstone of treatment in patients at risk for venous thromboembolism, inferior vena cava (IVC) filter use has increased exponentially over the last decade driven predominantly by the prophylactic use in patients at risk for venous thromboembolism despite limited evidence supporting this practice. The Predicting the Safety and Effectiveness of Inferior Vena Cava Filters (PRESERVE) Study is being implemented by the Society for Vascular Surgery, Society of Interventional Radiology, U.S. Food and Drug Administration, and several IVC filter manufactures to better understand the safety, effectiveness, and current patterns of real-world use of IVC filters. METHODS: The PRESERVE Study includes IVC filters from seven manufacturers: ALN (ALN ± hook), Argon (Option Elite), B. Braun (LP, Vena Tech Convertible), CR Bard (Denali), Cook (Gunther Tulip), Cordis (OptEase, TrapEase), and Philips Volcano (Crux). The indications for filter placement, filter brand, complications, stability, frequency and success of retrieval, and clinical effectiveness of each filter will be recorded. Approximately 2100 patients (300 for each filter brand included in the study) are intended to be enrolled at 60 U.S. centers. RESULTS: Men and women age 18 years or older requiring IVC filters for prevention of venous thromboembolism will be included in the study if no contrast allergy is present and they are willing to commit to the prescribed study follow-up. Participants will be evaluated at discharge, 3, 6, 12, 18, and 24 months after filter placement and/or 1 month after retrieval, which ever occurs first. Intravascular ultrasound examination or venography will be done before and after IVC filter placement, with abdominal plain film at 3 months, and contrast enhanced computed tomography scans at 12 and 24 months to evaluate filter stability. The primary safety end point is a composite of clinical end points, including freedom from perforation, embolization, thrombosis, recurrent DVT, and defined serious adverse events. Secondary end points include mechanical stability and procedure related complications at 3 months, major adverse events at 6, 12, 18, and 24 months, and filter tilt of more than 15° at any point. CONCLUSIONS: The PRESERVE Study represents the largest prospective study ever undertaken to investigate real-world outcomes with contemporary use of IVC filters. The investigators await results with the hope that it can improve patient care.


Assuntos
Implantação de Prótese/instrumentação , Filtros de Veia Cava , Veia Cava Inferior , Tromboembolia Venosa/prevenção & controle , Remoção de Dispositivo , Humanos , Estudos Multicêntricos como Assunto , Padrões de Prática Médica , Estudos Prospectivos , Desenho de Prótese , Falha de Prótese , Implantação de Prótese/efeitos adversos , Recidiva , Fatores de Risco , Fatores de Tempo , Resultado do Tratamento , Estados Unidos , Veia Cava Inferior/diagnóstico por imagem
15.
Sci Total Environ ; 698: 134197, 2020 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-31494425

RESUMO

Recently, a series of new photocatalysts have been developed for to combat diverse bio-recalcitrant contaminants and the inactivation of bacteria. Modeling photocatalytic processes is important to assess these materials, and to understand and optimize their performance. In this study, the recent literature is critically reviewed and analyzed to identify and compare methods of modeling photocatalytic performance. The Langmuir-Hinshelwood model (L-H) has been used in many studies to rationalize the degradation kinetics of single contaminants because it is the simplest model including both the adsorption equilibrium and degradation rates. Other studies report the development of more sophisticated variants of the L-H model that include the rates of catalyst excitation, recombination of electron-hole pairs, production of reactive oxygen species (ROS), and formation of by-products. Modified Chick-Watson (CW) and Hom models have been used by many researchers to include lag phases of bacteria in the description of disinfection kinetics. Artificial neural networks (ANNs) have been used to analyze the effects of operational conditions on photocatalyst performance. Moreover, response surface methodology (RSM) has been employed for experimental design, and optimization of operational conditions. We have reviewed and analyzed all available articles that model photocatalytic activity towards water pollution, summarized and put them in context, and recommended future research directions.

16.
Tech Vasc Interv Radiol ; 22(3): 154-161, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31623756

RESUMO

Endoscopy is a technique used by interventional radiology (IR) in only a few centers throughout the United States. When used by IR, endoscopy is most well-known for its role in the treatment of hepatobiliary disease. However, its use with relation to pathology involving the gastrointestinal, genitourinary, and musculoskeletal systems is gaining momentum among IR. The purpose of this article is to demonstrate the potential benefits of IR endoscopy in nonbiliary intervention. A literature review, not requiring IRB approval, was performed via PubMed and Ovid Medline databases using the search terms "interventional radiology-operated endoscopy," "interventional endoscopy," "interventional radiology," "genitourinary," and "gastrointestinal." Literature describing IR endoscopy involving the gastrointestinal, genitourinary, and musculoskeletal systems were identified and described. Nine peer-reviewed articles were identified. While few studies were identified, a general theme suggesting a synergistic relationship between IR and endoscopy was noted. More studies are needed to better understand the role of endoscopy as a technique in the IR suite.


Assuntos
Endoscopia/métodos , Doenças Urogenitais Femininas/terapia , Gastroenteropatias/terapia , Doenças Urogenitais Masculinas/terapia , Doenças Musculoesqueléticas/terapia , Radiografia Intervencionista/métodos , Adulto , Endoscopia/efeitos adversos , Endoscopia Gastrointestinal , Feminino , Doenças Urogenitais Femininas/diagnóstico por imagem , Gastroenteropatias/diagnóstico por imagem , Humanos , Masculino , Doenças Urogenitais Masculinas/diagnóstico por imagem , Doenças Musculoesqueléticas/diagnóstico por imagem , Radiografia Intervencionista/efeitos adversos , Resultado do Tratamento
17.
Phys Chem Chem Phys ; 21(42): 23466-23472, 2019 Nov 14.
Artigo em Inglês | MEDLINE | ID: mdl-31616875

RESUMO

The environmentally relevant n →π* transition in the nitrate anion is doubly forbidden by symmetry, as the Franck-Condon and first order vibronic coupling terms are both zero in the gas phase. Inclusion of the second order vibronic coupling term is therefore essential when calculating the oscillator strength. Here we have calculated an oscillator strength of 5.7 × 10-6. The second order vibronic coupling term is included by manually displacing the ground-state geometry simultaneously along two normal modes, Ql and Qk, in 19 × 19 steps, and calculating the transition dipole moment at each point by TD-DFT/ωB97XD/aug-cc-pVTZ and fitting to a polynomial in order to evaluate the second derivative with respect to Ql and Qk. In the aqueous phase the high symmetry of NO3- is broken and the first order term is no longer forbidden. However, the calculated solvated geometry still resembles the gas phase geometry and the calculated first order term does not contribute significantly to the overall oscillator strength of 1.9 × 10-6. This is a rare example of higher order vibronic coupling being more important than the lowest order term.

18.
Environ Sci Technol ; 53(16): 9636-9645, 2019 Aug 20.
Artigo em Inglês | MEDLINE | ID: mdl-31347357

RESUMO

California methane (CH4) emissions are quantified for three years from two tower networks and one aircraft campaign. We used backward trajectory simulations and a mesoscale Bayesian inverse model, initialized by three inventories, to achieve the emission quantification. Results show total statewide CH4 emissions of 2.05 ± 0.26 (at 95% confidence) Tg/yr, which is 1.14 to 1.47 times greater than the anthropogenic emission estimates by California Air Resource Board (CARB). Some of differences could be biogenic emissions, superemitter point sources, and other episodic emissions which may not be completely included in the CARB inventory. San Joaquin Valley (SJV) has the largest CH4 emissions (0.94 ± 0.18 Tg/yr), followed by the South Coast Air Basin, the Sacramento Valley, and the San Francisco Bay Area at 0.39 ± 0.18, 0.21 ± 0.04, and 0.16 ± 0.05 Tg/yr, respectively. The dairy and oil/gas production sources in the SJV contribute 0.44 ± 0.36 and 0.22 ± 0.23 Tg CH4/yr, respectively. This study has important policy implications for regulatory programs, as it provides a thorough multiyear evaluation of the emissions inventory using independent atmospheric measurements and investigates the utility of a complementary multiplatform approach in understanding the spatial and temporal patterns of CH4 emissions in the state and identifies opportunities for the expansion and applications of the monitoring network.


Assuntos
Poluentes Atmosféricos , Metano , Aeronaves , Teorema de Bayes , California , São Francisco
19.
Int J Vasc Med ; 2019: 5795148, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31263598

RESUMO

The Sentry inferior vena cava (IVC) filter is designed to provide temporary protection against pulmonary embolism (PE) during transient high-risk periods and then to bioconvert after 60 days after implantation. At the time of bioconversion, the device's nitinol arms retract from the filtering position into the caval wall. Subsequently, the stable stent-like nitinol frame is endothelialized. The Sentry bioconvertible IVC filter has been evaluated in a multicenter investigational-device-exemption pivotal trial (NCT01975090) of 129 patients with documented deep vein thrombosis (DVT) or PE, or at temporary risk of developing DVT or PE, and with contraindications to anticoagulation. Successful filter conversion was observed in 95.7% of patients at 6 months (110/115) and 96.4% at 12 months (106/110). Through 12 months, there were no cases of symptomatic PE. The rationale for development of the Sentry bioconvertible device includes the following considerations: (1) the period of highest risk of PE for the vast majority of patients occurs within the first 60 days after an index event, with most of the PEs occurring in the first 30 days; (2) the design of retrievable IVC filters to support their removal after a transitory high-PE-risk period has, in practice, been associated with insecure filter dynamics and time-dependent complications including tilting, fracture, embolization, migration, and IVC perforation; (3) most retrievable IVC filters are placed for temporary protection, but for a variety of reasons they are not removed in any more than half of implanted patients, and when removal is attempted, the procedure is not always successful even with advanced techniques; and (4) analysis of Medicare hospital data suggests that payment for the retrieval procedure does not routinely compensate for expense. The Sentry device is not intended for removal after bioconversion. In initial clinical use, complications have been limited. Long-term results for the Sentry bioconvertible IVC filter are anticipated soon.

20.
Cancers (Basel) ; 11(6)2019 Jun 22.
Artigo em Inglês | MEDLINE | ID: mdl-31234476

RESUMO

Hepatocellular carcinoma (HCC) is a leading cause of new cancer diagnoses in the United States, with an incidence that is expected to rise. The etiology of HCC is varied and can lead to differences between patients in terms of presentation and natural history. Subsequently, physicians treating these patients need to consider a variety of disease and patient characteristics when they select from the many different treatment options that are available for these patients. At the same time, the treatment landscape for patients with HCC, particularly those with unresectable HCC, has been rapidly evolving as new, evidence-based options become available. The treatment plan for patients with HCC can include surgery, transplant, ablation, transarterial chemoembolization, transarterial radioembolization, radiation therapy, and/or systemic therapies. Implementing these different modalities, where the optimal sequence and/or combination has not been defined, requires coordination between physicians with different specialties, including interventional radiologists, hepatologists, and surgical and medical oncologists. As such, the implementation of a multidisciplinary team is necessary to develop a comprehensive care plan for patients, especially those with unresectable HCC.

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