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1.
Anal Chem ; 96(27): 10886-10892, 2024 Jul 09.
Artigo em Inglês | MEDLINE | ID: mdl-38925554

RESUMO

Scanning electrochemical microscopy (SECM) and scanning electrochemical cell microscopy (SECCM) were integrated in a single bifunctional probe for simultaneous mapping of the oxygen reduction current and the oxidation current of the produced H2O2. The dual probe is fabricated from a double-barrel θ capillary, comprising one open barrel filled with the electrolyte and another filled with pyrolytic carbon. Pt is deposited with a gas injection system (GIS) at the end of the carbon barrel. The probe integrates the advantages of both SECM and SECCM by forming an electrochemical droplet cell that embeds the Pt working electrode of the carbon barrel directly into the electrolyte meniscus formed upon sample contact from the electrolyte barrel. The versatility of the dual probe is demonstrated by mapping the oxygen reduction reaction (ORR) current and the H2O2 oxidation current of a Pt microstrip on a gold substrate. This allows simultaneous localized electrochemical measurements, highlighting the potential of the dual probe for broader applications in characterizing the electrocatalytic properties of materials.

2.
Implement Sci Commun ; 5(1): 62, 2024 Jun 06.
Artigo em Inglês | MEDLINE | ID: mdl-38845055

RESUMO

As global adoption of antiretroviral therapy extends the lifespan of People Living with HIV (PLHIV) through viral suppression, the risk of comorbid conditions such as hypertension has risen, creating a need for effective, scalable interventions to manage comorbidities in PLHIV. The Heart, Lung, and Blood Co-morbiditieS Implementation Models in People Living with HIV (HLB-SIMPLe) Alliance has been funded by the National Heart, Lung, and Blood Institute (NHLBI) and the Fogarty International Center (FIC) since September 2020. The Alliance was created to conduct late-stage implementation research to contextualize, implement, and evaluate evidence-based strategies to integrate the diagnosis, treatment, and control of cardiovascular diseases, particularly hypertension, in PLHIV in low- and middle-income countries (LMICs).The Alliance consists of six individually-funded clinical trial cooperative agreement research projects based in Botswana, Mozambique, Nigeria, South Africa, Uganda, and Zambia; the Research Coordinating Center; and personnel from NIH, NHLBI, and FIC (the Federal Team). The Federal Team works together with the members of the seven cooperative agreements which comprise the alliance. The Federal Team includes program officials, project scientists, grant management officials and clinical trial specialists. This Alliance of research scientists, trainees, and administrators works collaboratively to provide and support venues for ongoing information sharing within and across the clinical trials, training and capacity building in research methods, publications, data harmonization, and community engagement. The goal is to leverage shared learning to achieve collective success, where the resulting science and training are greater with an Alliance structure rather than what would be expected from isolated and unconnected individual research projects.In this manuscript, we describe how the Research Coordinating Center performs the role of providing organizational efficiencies, scientific technical assistance, research capacity building, operational coordination, and leadership to support research and training activities in this multi-project cooperative research Alliance. We outline challenges and opportunities during the initial phases of coordinating research and training in the HLB-SIMPLe Alliance, including those most relevant to dissemination and implementation researchers.

3.
Small Methods ; 8(7): e2301284, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38155148

RESUMO

High-entropy alloys (HEAs), especially in the form of compositional complex solid solutions (CCSS), have gained attention in the field of electrocatalysis. However, exploring their vast composition space concerning their electrocatalytic properties imposes significant challenges. Scanning electrochemical cell microscopy (SECCM) offers high-speed electrochemical analysis on surface areas with a lateral resolution down to tens of nm. However, high-precision piezo positioners often used for the motion of the tip limit the area of SECCM scans to the motion range of the piezo positioners which is typically a few tens of microns. To bridge this experimental gap, the study proposes a long-range SECCM system with a rapid gas-exchange environmental cell for high-throughput electrochemical characterization of 100 mm diameter HEA thin-film material libraries (ML) obtained by combinatorial co-sputtering. Due to the gas-liquid interface at the positioned SECCM droplet on the sample, high-throughput evaluation under industrial current density conditions becomes feasible. This allows the direct correlation between electrocatalytic activity and material composition with high statistical reliability. The multidimensional data obtained accelerates materials discovery, development, and optimization.

4.
Implement Sci Commun ; 4(1): 132, 2023 Nov 06.
Artigo em Inglês | MEDLINE | ID: mdl-37932842

RESUMO

BACKGROUND: As a relatively new field, dissemination and implementation research has not been included as a separate study design category for ethical consideration compared with clinical and social/behavioral research, yet it should be based on unique study designs, targets of intervention, and corresponding risks. MAIN TEXT: Research teams conducting dissemination and implementation research have raised important questions related to the responsible conduct of research such as collecting informed consent, site monitoring, identifying and mitigating risks of unintended consequences, and adverse event ascertainment and reporting in dissemination and implementation research. In this commentary, we highlight the need for guidance and consensus standards on ethical issues in dissemination and implementation research and describe some ethical domains and relevant questions in dissemination and implementation research. Additionally, we propose a process for conceptual development and a research agenda to create consensus standards for the responsible conduct of research for dissemination and implementation research. CONCLUSION: Thorough research is needed to understand the depth of ethical issues in dissemination and implementation research. A consensus-seeking process will be needed to develop new bioethical standards that carefully identify, measure, and mitigate unintended consequences in dissemination and implementation research.

5.
Am J Surg ; 2023 Nov 10.
Artigo em Inglês | MEDLINE | ID: mdl-37981518

RESUMO

BACKGROUND: The surgical profession is plagued with a high prevalence of work-related musculoskeletal disorders. While numerous interventions have been tested over the years, surgical ergonomics education is still uncommon. METHODS: The available literature on surgical ergonomics was reviewed, and with input from surgeons, recommendations from the review were used to create pictorial reminders for open, laparoscopic, and robot-assisted surgical modalities. These simple pictorial ergonomic recommendations were then assessed for practicality by residents and surgeons. RESULTS: A review of the current literature on surgical ergonomics covered evidence-based ergonomic recommendations on equipment during open and laparoscopic surgery, as well as proper adjustment of the surgical robot for robot-assisted surgeries. Ergonomic operative postures for the three modalities were examined, illustrated, and assessed. CONCLUSIONS: The resulting illustrations of ergonomic guidelines across surgical modalities may be employed in developing ergonomic education materials and improving the identification and mitigation of ergonomic risks in the operating room.

6.
Angew Chem Int Ed Engl ; 62(39): e202310069, 2023 Sep 25.
Artigo em Inglês | MEDLINE | ID: mdl-37537136

RESUMO

The vast possibilities in the elemental combinations of high-entropy alloys (HEAs) make it essential to discover activity descriptors for establishing rational electrocatalyst design principles. Despite the increasing attention on the potential of zero charge (PZC) of hydrogen evolution reaction (HER) electrocatalyst, neither the PZC of HEAs nor the impact of the PZC on the HER activity at HEAs has been described. Here, we use scanning electrochemical cell microscopy (SECCM) to determine the PZC and the HER activities of various elemental compositions of a Pt-Pd-Ru-Ir-Ag thin-film HEA materials library (HEA-ML) with high statistical reliability. Interestingly, the PZC of Pt-Pd-Ru-Ir-Ag is linearly correlated with its composition-weighted average work function. The HER current density in acidic media positively correlates with the PZC, which can be explained by the preconcentration of H+ in the electrical double layer at potentials negative of the PZC.

9.
Chem Asian J ; 18(13): e202300256, 2023 Jul 03.
Artigo em Inglês | MEDLINE | ID: mdl-37199670

RESUMO

The selectivity of catalytic materials suitable for oxygen reduction potential of bio-electrochemical systems is very affluent. Therefore, exploring magnetite and static magnetic field as alternative option to promote microbial electron transfer comes in handy. In this study, the application of magnetite-nanoparticles and a static magnetic field on a microbial fuel cell (MFC) in anaerobic digestion was investigated. The experimental set-up included four 1 L biochemical methane potential tests: a) MFC, b) MFC with magnetite-nanoparticles (MFCM), c) MFC with magnetite-nanoparticles and magnet (MFCMM), and d) control. The highest biogas production obtained was 545.2 mL/g VSfed in the MFCMM digester, which was substantially greater than the 117.7 mL/g VSfed of the control. This was accompanied by high contaminant removals for chemical oxygen demand (COD) of 97.3%, total solids (TS) of 97.4%, total suspended solids (TSS) of 88.7%, volatile solids (VS) 96.1%, and color of 70.2%. The electrochemical efficiency analysis revealed greater maximum current density of 12.5 mA/m2 and coulombic efficiency of 94.4% for the MFCMM. Kinetically, the cumulative biogas produced data obtained were well fitted on the modified Gompertz models and the greatest coefficient of determination (R2 =0.990) was obtained in the MFCMM. Therefore, the application of magnetite-nanoparticles and static magnetic field on MFC showed a high potential for bioelectrochemical methane production and contaminant removal for sewage sludge.


Assuntos
Fontes de Energia Bioelétrica , Nanopartículas de Magnetita , Anaerobiose , Óxido Ferroso-Férrico , Biocombustíveis , Reatores Biológicos , Esgotos , Metano
10.
Angew Chem Int Ed Engl ; 62(28): e202305982, 2023 Jul 10.
Artigo em Inglês | MEDLINE | ID: mdl-37178313

RESUMO

The role of ß-CoOOH crystallographic orientations in catalytic activity for the oxygen evolution reaction (OER) remains elusive. We combine correlative electron backscatter diffraction/scanning electrochemical cell microscopy with X-ray photoelectron spectroscopy, transmission electron microscopy, and atom probe tomography to establish the structure-activity relationships of various faceted ß-CoOOH formed on a Co microelectrode under OER conditions. We reveal that ≈6 nm ß-CoOOH(01 1 ‾ ${\bar{1}}$ 0), grown on [ 1 ‾ 2 1 ‾ ${\bar{1}2\bar{1}}$ 0]-oriented Co, exhibits higher OER activity than ≈3 nm ß-CoOOH(10 1 ‾ ${\bar{1}}$ 3) or ≈6 nm ß-CoOOH(0006) formed on [02 2 ‾ 1 ] ${\bar{2}1]}$ - and [0001]-oriented Co, respectively. This arises from higher amounts of incorporated hydroxyl ions and more easily reducible CoIII -O sites present in ß-CoOOH(01 1 ‾ ${\bar{1}}$ 0) than those in the latter two oxyhydroxide facets. Our correlative multimodal approach shows great promise in linking local activity with atomic-scale details of structure, thickness and composition of active species, which opens opportunities to design pre-catalysts with preferred defects that promote the formation of the most active OER species.

11.
Appl Ergon ; 111: 104049, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37210778

RESUMO

This study investigated vascular surgeon workload and its association with specific procedural drivers over different procedure types. Thirteen attending vascular surgeons (two females) were emailed a survey over a 3-month period. Data from 253 surgical procedures (118 open, 85 endovascular, 18 hybrid, and 32 venous) revealed high physical and cognitive workload among vascular surgeons. Based on the statistically significant findings and similar non-significant trends in the data (significance level of 0.01), open and hybrid vascular procedures showed higher levels of physical and cognitive workload compared to venous cases, while endovascular procedures were relatively more moderate. Additionally, the workload subscales for five subcategories of open procedures (e.g., arteriovenous access) as well as three subcategories of endovascular procedures (e.g., aortic) were compared. The granularity of the intraoperative workload drivers across various vascular procedure types and adjunct equipment could be the key to create targeted ergonomic interventions to reduce workload during vascular surgeries.


Assuntos
Cirurgiões , Carga de Trabalho , Feminino , Humanos , Carga de Trabalho/psicologia , Procedimentos Cirúrgicos Vasculares , Ergonomia , Cirurgiões/psicologia , Inquéritos e Questionários
12.
J Chem Phys ; 158(13): 134707, 2023 Apr 07.
Artigo em Inglês | MEDLINE | ID: mdl-37031154

RESUMO

Room temperature ionic liquids (RT-ILs) are promising electrolytes for electrocatalysis. Understanding the effects of the electrode-electrolyte interface structure on electrocatalysis in RT-ILs is important. Ultrafast mass transport of redox species in N-methyl-N-ethyl-pyrrolidinium polybromide (MEPBr2n+1) enabled evaluation of the reorganization energy (λ), which reflects the solvation structure in the inner Helmholtz plane (IHP). λ was achieved by fitting the electron transfer rate-limited voltammogram at a Pt ultramicroelectrode (UME) to the Marcus-Hush-Chidsey model for heterogeneous electron transfer kinetics. However, it is time-consuming or even impossible to prepare electrode materials, including alloys of numerous compositions in the form of UME, for each experiment. Herein, we report a method to evaluate the λ of MEPBr2n+1 by scanning electrochemical cell microscopy (SECCM), which allows high throughput electrochemical measurements using a single electrode with high spatial resolution. Fast mass transport in the nanosized SECCM tip is critical for achieving heterogeneous electron transfer-limited voltammograms. Furthermore, investigating λ on a high-entropy alloy materials library composed of Pt, Pd, Ru, Ir, and Ag suggests a negative correlation between λ and the work function. Given that the potential of zero charge correlates with the work function of electrodes, this can be attributed to the surface-charge sensitive ionic structure in the IHP of MEPBr2n+1, modulating the solvation energy of the redox-active species in the IHP.

13.
Membranes (Basel) ; 13(4)2023 Apr 14.
Artigo em Inglês | MEDLINE | ID: mdl-37103859

RESUMO

Increased affordability, smaller footprint, and high permeability quality that meets stringent water quality standards have accelerated the uptake of membranes in water treatment. Moreover, low pressure, gravity-based microfiltration (MF) and ultrafiltration (UF) membranes eliminate the use of electricity and pumps. However, MF and UF processes remove contaminants by size exclusion, based on membrane pore size. This limits their application in the removal of smaller matter or even harmful microorganisms. There is a need to enhance the membrane properties to meet needs such as adequate disinfection, flux amelioration, and reduced membrane fouling. To achieve these, the incorporation of nanoparticles with unique properties in membranes has potential. Herein, we review recent developments in the impregnation of polymeric and ceramic microfiltration and ultrafiltration membranes with silver nanoparticles that are applied in water treatment. We critically evaluated the potential of these membranes in enhanced antifouling, increased permeability quality and flux compared to uncoated membranes. Despite the intensive research in this area, most studies have been performed at laboratory scale for short periods of time. There is a need for studies that assess the long-term stability of the nanoparticles and the impact on disinfection and antifouling performance. These challenges are addressed in this study and future directions.

14.
Microorganisms ; 11(3)2023 Mar 02.
Artigo em Inglês | MEDLINE | ID: mdl-36985216

RESUMO

In this paper, the application of magnetite-nanoparticles and a microbial fuel cell (MFC) was studied on the anaerobic digestion (AD) of sewage sludge. The experimental set-up included six 1 L biochemical methane potential (BMP) tests with different external resistors: (a) 100 Ω, (b) 300 Ω, (c) 500 Ω, (d) 800 Ω, (e) 1000 Ω, and (f) a control with no external resistor. The BMP tests were carried out using digesters with a working volume of 0.8 L fed with 0.5 L substrate, 0.3 L inoculum, and 0.53 g magnetite-nanoparticles. The results suggested that the ultimate biogas generation reached 692.7 mL/g VSfed in the 500 Ω digester, which was substantially greater than the 102.6 mL/g VSfed of the control. The electrochemical efficiency analysis also demonstrated higher coulombic efficiency (81.2%) and maximum power density (30.17 mW/ m2) for the 500 Ω digester. The digester also revealed a higher maximum voltage generation of 0.431 V, which was approximately 12.7 times the 0.034 V of the lowest-performing MFC (100 Ω digester). In terms of contaminants removed, the best-performing digester was the digester with 500 Ω, which reduced contaminants by more than 89% on COD, TS, VS, TSS and color. In terms of cost-benefit analysis, this digester produced the highest annual energy profit (48.22 ZAR/kWh or 3.45 USD/kWh). This infers the application of magnetite-nanoparticles and MFC on the AD of sewage sludge is very promising for biogas production. The digester with an external resistor of 500 Ω showed a high potential for use in bioelectrochemical biogas generation and contaminant removal for sewage sludge.

15.
Molecules ; 28(6)2023 Mar 22.
Artigo em Inglês | MEDLINE | ID: mdl-36985825

RESUMO

A microbial fuel cell (MFC) is a bioelectrochemical system that can be employed for the generation of electrical energy under microbial activity during wastewater treatment practices. The optimization of electrode spacing is perhaps key to enhancing the performance of an MFC. In this study, electrode spacing was evaluated to determine its effect on the performance of MFCs. The experimental work was conducted utilizing batch digesters with electrode spacings of 2.0 cm, 4.0 cm, 6.0 cm, and 8.0 cm. The results demonstrate that the performance of the MFC improved when the electrode spacing increased from 2.0 to 6.0 cm. However, the efficiency decreased after 6.0 cm. The digester with an electrode spacing of 6.0 cm enhanced the efficiency of the MFC, which led to smaller internal resistance and greater biogas production of 662.4 mL/g VSfed. The electrochemical efficiency analysis demonstrated higher coulombic efficiency (68.7%) and electrical conductivity (177.9 µS/cm) for the 6.0 cm, which was evident from the enrichment of electrochemically active microorganisms. With regards to toxic contaminant removal, the same digester also performed well, revealing removals of over 83% for chemical oxygen demand (COD), total solids (TS), total suspended solids (TSS), and volatile solids (VS). Therefore, these results indicate that electrode spacing is a factor affecting the performance of an MFC, with an electrode spacing of 6.0 cm revealing the greatest potential to maximize biogas generation and the degradability of wastewater biochemical matter.


Assuntos
Fontes de Energia Bioelétrica , Óxido Ferroso-Férrico , Biocombustíveis , Eletricidade , Eletrodos
16.
Int J Mol Sci ; 24(5)2023 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-36902185

RESUMO

The interspecies electron transfer (IET) between microbes and archaea is the key to how the anaerobic digestion process performs. However, renewable energy technology that utilizes the application of a bioelectrochemical system together with anaerobic additives such as magnetite-nanoparticles can promote both direct interspecies electron transfer (DIET) as well as indirect interspecies electron transfer (IIET). This has several advantages, including higher removal of toxic pollutants present in municipal wastewater, higher biomass to renewable energy conversion, and greater electrochemical efficiencies. This review explores the synergistic influence of bioelectrochemical systems and anaerobic additives on the anaerobic digestion of complex substrates such as sewage sludge. The review discussions present the mechanisms and limitations of the conventional anaerobic digestion process. In addition, the applicability of additives in syntrophic, metabolic, catalytic, enzymatic, and cation exchange activities of the anaerobic digestion process are highlighted. The synergistic effect of bio-additives and operational factors of the bioelectrochemical system is explored. It is elucidated that a bioelectrochemical system coupled with nanomaterial additives can increase biogas-methane potential compared to anaerobic digestion. Therefore, the prospects of a bioelectrochemical system for wastewater require research attention.


Assuntos
Reatores Biológicos , Águas Residuárias , Anaerobiose , Esgotos , Archaea , Metano
17.
Health Promot Pract ; 24(5): 932-943, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-35533246

RESUMO

HIV represents a significant health burden in the United States. In 2012, the Centers for Disease Control and Prevention (CDC) stopped recommending many once-promoted interventions as part of a shift from one HIV intervention policy, Diffusion of Effective Behavioral Interventions (DEBI), to another, High Impact Prevention (HIP). Twenty-nine staff members from 10 organizations were interviewed to explore how organizations reacted to this shift. Three major themes emerged: (1) Personal experience, community assessment, and epidemiological evidence influenced organizations' perceptions of efficacy and preference for earlier interventions. (2) Organizations were concerned that HIP interventions were not a good fit for their priority populations. (3) Organizations were frustrated with the top-down approach by the CDC prioritizing HIP interventions over earlier interventions. These results indicate that organizations continue to see value in and provide DEBI interventions. In addition, a more participatory process incorporating qualitative evidence and organizations' experiences may be necessary to achieve widespread de-implementation of DEBI interventions.


Assuntos
Infecções por HIV , Estados Unidos , Humanos , Infecções por HIV/prevenção & controle , Políticas , Centers for Disease Control and Prevention, U.S.
18.
J Reconstr Microsurg ; 39(6): 453-461, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-36509101

RESUMO

BACKGROUND: This study compared the ergonomics of surgeons during deep inferior epigastric perforator (DIEP) flap surgery using either baseline equipment (loupes, headlights, and an operating microscope) or an exoscope. Plastic surgeons may be at high risk of musculoskeletal problems. Recent studies indicate that adopting an exoscope may significantly improve surgeon postures and ergonomics. METHODS: Postural exposures, using inertial measurement units at the neck, torso, and shoulders, were calculated in addition to the surgeons' subjective physical and cognitive workload. An ergonomic risk score on a scale of 1 (lowest) to 4 (highest) was calculated for each of the postures observed. Data from 23 bilateral DIEP flap surgeries (10 baseline and 13 exoscope) were collected. RESULTS: The neck and torso risk scores decreased significantly during abdominal flap harvest and chest dissection, while right shoulder risk scores increased during the abdominal flap harvest for exoscope DIEP flap procedures compared with. Exoscope anastomoses demonstrated higher neck, right shoulder, and left shoulder risk scores. The results from the survey for the "surgeon at abdomen" showed that the usage of exoscopes was associated with decreased performance and increased mental demand, temporal demand, and effort. However, the results from the "surgeon at chest" showed that the usage of exoscopes was associated with lower physical demand and fatigue, potentially due to differences in surgeon preference. CONCLUSION: Our study revealed some objective evidence for the ergonomic benefits of exoscope; however, this is dependent on the tasks the surgeon is performing. Additionally, personal preferences may be an important factor to be considered in the ergonomic evaluation of the exoscope.


Assuntos
Mamoplastia , Retalho Perfurante , Mamoplastia/métodos , Ergonomia , Abdome , Pescoço , Artérias Epigástricas
19.
Angew Chem Int Ed Engl ; 62(9): e202214493, 2023 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-36469735

RESUMO

Anatase TiO2 is a promising material for Li-ion (Li+ ) batteries with fast charging capability. However, Li+ (de)intercalation dynamics in TiO2 remain elusive and reported diffusivities span many orders of magnitude. Here, we develop a smart protocol for scanning electrochemical cell microscopy (SECCM) with in situ optical microscopy (OM) to enable the high-throughput charge/discharge analysis of single TiO2 nanoparticle clusters. Directly probing active nanoparticles revealed that TiO2 with a size of ≈50 nm can store over 30 % of the theoretical capacity at an extremely fast charge/discharge rate of ≈100 C. This finding of fast Li+ storage in TiO2 particles strengthens its potential for fast-charging batteries. More generally, smart SECCM-OM should find wide applications for high-throughput electrochemical screening of nanostructured materials.

20.
Adv Mater ; 35(9): e2207635, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36542651

RESUMO

Polyelemental material systems, specifically high-entropy alloys, promise unprecedented properties. Due to almost unlimited combinatorial possibilities, their exploration and exploitation is hard. This challenge is addressed by co-sputtering combined with shadow masking to produce a multitude of microscale combinatorial libraries in one deposition process. These thin-film composition spreads on the microscale cover unprecedented compositional ranges of high-entropy alloy systems and enable high-throughput characterization of thousands of compositions for electrocatalytic energy conversion reactions using nanoscale scanning electrochemical cell microscopy. The exemplary exploration of the composition space of two high-entropy alloy systems provides electrocatalytic activity maps for hydrogen evolution and oxygen evolution as well as oxygen reduction reactions. Activity optima in the system Ru-Rh-Pd-Ir-Pt are identified, and active noble-metal lean compositions in the system Co-Ni-Mo-Pd-Pt are discovered. This illustrates that the proposed microlibraries are a holistic discovery platform to master the multidimensionality challenge of polyelemental systems.

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