Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 56
Filtrar
Mais filtros

Base de dados
País/Região como assunto
Tipo de documento
Intervalo de ano de publicação
1.
J Environ Manage ; 323: 116190, 2022 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-36261961

RESUMO

The Wisconsin Rapids Wastewater Treatment Plant (WRWWTP) is faced with a more stringent effluent phosphorus requirement that will drive capital investment between 2020 and 2025. The facility will need to achieve a monthly average value of 0.36 mg L-1 of total phosphorus (TP). While the facility has sufficient influent carbon to drive a conventional enhanced biological phosphorus removal (EBPR) configuration, the existing infrastructure makes the addition of influent selector zones cost prohibitive. Underutilized aeration basin capacity was repurposed for testing return activated sludge (RAS) fermentation. The WRWWTP began pilot testing of RAS fermentation in April 2021. The facility moved through a series of operational setpoints to optimize phosphorus removal in a sidestream RAS (SSR) configuration, including RAS diversion, decrease of DO in aeration basins and chemical dosing shutoff. One of the key implementations was the addition of cranberry syrup waste to provide additional carbon for RAS fermentation, converting the process to a SSR plus carbon (SSRC) configuration. By the end of the testing period, effluent total phosphorus was averaging less than 0.4 mg L-1 with no chemical addition. A model was developed in the SUMO platform and was used to capture orthophosphate trends during the testing period. The model investigated microbial population dynamics and found that the operational changes including RAS diversion, chemical dosing shutoff and cranberry syrup waste addition impacted the enrichment of phosphorus accumulating organisms (PAO). After performing a sensitivity analysis on hydrolysis parameters, the predicted hydrolysis rate around 1.8-1.9 mg COD g VSS-1 hr-1 was found to match the batch rate testing data. This is the first study where cranberry syrup waste was used to successfully enhance EBPR performance, resulting in 90% TP removal. While further research is needed regarding the composition of the waste matrix and the microbial community composition, this expands the routes for resource recovery in the field of wastewater treatment.


Assuntos
Esgotos , Vaccinium macrocarpon , Esgotos/química , Reatores Biológicos , Wisconsin , Fósforo , Carbono , Fosfatos , Águas Residuárias , Eliminação de Resíduos Líquidos/métodos
2.
Med Teach ; 43(9): 1010-1018, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-33161823

RESUMO

Peripheral Intravenous access (PIV) is a procedure undertaken by Medical Practitioners and Non-Medical Practitioners. Traditional PIV uses a visual and tactile technique to locate blood vessels close to the surface of the skin. Chronic medical conditions, dehydration, obesity and recurrent intravenous access can make PIV challenging. Ultrasound (US) guided PIV is recommended to aid the identification of the arm arteries and veins and improve the success rate of needle placement in difficult cases. Medical and non-medical schools, and hospital organisations, are recognising the importance of US guided PIV education for undergraduate and postgraduate Medical and Non-Medical Practitioners. This to promote independence, efficiency and to improve patient safety. The aim of this 12 tips article is to highlight the considerations and practicalities of integrating and delivering, a practical based skills (PBS) session, on the use of US guided practice as an adjunct in difficult PIV, into the undergraduate medical education curricula.


Assuntos
Cateterismo Periférico , Educação de Graduação em Medicina , Competência Clínica , Humanos , Ultrassonografia , Ultrassonografia de Intervenção
3.
Pharm Res ; 37(11): 228, 2020 Oct 23.
Artigo em Inglês | MEDLINE | ID: mdl-33098017

RESUMO

PURPOSES: The main purposes of this article are to describe an unprecedented phenomenon in which significant amount of a shoulder peak impurity was observed during normal non-reducing capillary electrophoresis-sodium dodecyl sulfate (CE-SDS) analysis of a recombinant fusion protein X, and to evaluate the root cause for this phenomenon. METHODS: A series of experiments were conducted to study the nature of this degradation. Effects of iodoacetamide (IAM), heating temperature, duration, and SDS on the formation of this specific impurity were evaluated using a variety of characterization techniques. RESULTS: The formation of the impurity as observed in CE-SDS was actually due to alkylation of lysine and serine residues with IAM, as confirmed by peptide mapping and LC-MS/MS, which increased the molecular weight and therefore decreased the electrophoretic mobility. The amount of impurity was also strongly dependent on sample preparation conditions including the presence or absence of SDS. CONCLUSIONS: Our study clearly suggested that even though IAM has been used extensively as an alkylation reagent in the traditional non-reducing CE-SDS analysis of monoclonal antibodies and other proteins, alkylation with IAM could potentially lead to additional impurity peak, and therefore complicating analysis. Therefore, before performing CE-SDS and other analyses, the effects of sample preparation procedures on analytical results must be evaluated. For protein X, IAM should be excluded for CE-SDS analysis.


Assuntos
Proteínas Recombinantes/química , Dodecilsulfato de Sódio/química , Anticorpos Monoclonais/química , Cromatografia Líquida/métodos , Eletroforese Capilar/métodos , Eletroforese em Gel de Poliacrilamida/métodos , Espectrometria de Massas em Tandem/métodos
4.
Artif Organs ; 44(7): 709-716, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31970800

RESUMO

Only a small number of English hospitals provide postcardiotomy venoarterial extracorporeal membrane oxygenation (VA-ECMO) and there are doubts about its efficacy and safety. The aim of this service evaluation was to determine local survival rates and report on patient demographics. This was a retrospective service evaluation of prospectively recorded routine clinical data from a tertiary cardiothoracic center in the United Kingdom offering services including cardiac and thoracic surgery, heart and lung transplantation, venovenous extracorporeal membrane oxygenation (VV-ECMO) for respiratory failure, and all types of mechanical circulatory support. In six years, 39 patients were supported with VA-ECMO for refractory postcardiotomy cardiogenic shock (PCCS). We analyzed survival data and looked for associations between survival rates and patient characteristics. The intervention was venoarterial-ECMO in patients with PCCS either following weaning from cardiopulmonary bypass or following a trial of inotropes and intra-aortic balloon counterpulsation on the intensive care unit. 30-day, hospital discharge, 1-year and 2-year survivals were 51.3%, 41%, 37.5%, and 38.5%, respectively. The median (IQR [range]) duration of support was 6 (4-9 [1-35]) days. Nonsurvival was associated with advanced age, shorter intensive care length of stay, and the requirement for postoperative hemofiltration. Reasonable survival rates can be achieved in selected patients who may have been expected to have a worse mortality without VA-ECMO. We suggest postoperative VA-ECMO should be available to all patients undergoing cardiac surgery be it in their own center or through an established pathway to a specialist center.


Assuntos
Procedimentos Cirúrgicos Cardíacos/efeitos adversos , Oxigenação por Membrana Extracorpórea/efeitos adversos , Complicações Pós-Operatórias/terapia , Choque Cardiogênico/terapia , Centros de Atenção Terciária/organização & administração , Adulto , Fatores Etários , Idoso , Feminino , Hemofiltração/estatística & dados numéricos , Mortalidade Hospitalar , Humanos , Masculino , Pessoa de Meia-Idade , Complicações Pós-Operatórias/etiologia , Complicações Pós-Operatórias/mortalidade , Avaliação de Programas e Projetos de Saúde , Estudos Retrospectivos , Fatores de Risco , Choque Cardiogênico/etiologia , Choque Cardiogênico/mortalidade , Taxa de Sobrevida , Centros de Atenção Terciária/estatística & dados numéricos , Resultado do Tratamento
5.
Perfusion ; 35(3): 197-201, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-31480930

RESUMO

Extracorporeal membrane oxygenation is a safe modality of cardiorespiratory support for lung transplantation, with a reduction in coagulopathy and transfusion requirement when compared with cardiopulmonary bypass. In some scenarios, in lung transplantation, there are advantages to the use of cardiopulmonary bypass, which allows cardiac decompression, filtering of embolic air, easy addition and removal of volume, and a means to immediately reintroduce lost blood into circulation. We describe a novel circuit which allows safe and easy switch between modalities without prolonged interruption of flow. This circuit offers a safety net during surgery to minimise the risks influencing the use of extracorporeal membrane oxygenation.


Assuntos
Oxigenação por Membrana Extracorpórea/métodos , Transplante de Pulmão/métodos , Feminino , Humanos , Pessoa de Meia-Idade , Resultado do Tratamento
6.
Sensors (Basel) ; 18(10)2018 Oct 17.
Artigo em Inglês | MEDLINE | ID: mdl-30336609

RESUMO

Bright surfaces across the western U.S. lead to uncertainties in satellite derived aerosol optical depth (AOD) where AOD is typically overestimated. With this in mind, a compact and portable instrument was developed to measure surface albedo on an unmanned aircraft system (UAS). This spectral albedometer uses two Hamamatsu micro-spectrometers (range: 340⁻780 nm) for measuring incident and reflected solar radiation at the surface. The instrument was deployed on 5 October 2017 in Nevada's Black Rock Desert (BRD) to investigate a region of known high surface reflectance for comparison with albedo products from satellites. It was found that satellite retrievals underestimate surface reflectance compared to the UAS mounted albedometer. To highlight the importance of surface reflectance on the AOD from satellite retrieval algorithms, a 1-D radiative transfer model was used. The simple model was used to determine the sensitivity of AOD with respect to the change in albedo and indicates a large sensitivity of AOD retrievals to surface reflectance for certain combinations of surface albedo and aerosol optical properties. This demonstrates the need to increase the number of surface albedo measurements and an intensive evaluation of albedo satellite retrievals to improve satellite-derived AOD. The portable instrument is suitable for other applications as well.

7.
Water Sci Technol ; 78(10): 2119-2130, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30629540

RESUMO

This paper summarizes recent developments in biological phosphorus removal modelling, with special attention to side-stream enhanced biological phosphorus removal (S2EBPR) systems on which previous models proved to be ineffective without case-by-case parameter adjustments. Through the research and experience of experts and practitioners, a new bio-kinetic model was developed including an additional group of biomass (glycogen accumulating organisms - GAOs) and new processes (such as aerobic and anoxic maintenance for PAO and GAO; enhanced denitrification processes; fermentation by PAOs which - along with PAO selection - is driven by oxidation-reduction potential (ORP)). This model successfully described various conditions in laboratory measurements and full plant data. The calibration data set is provided by Clean Water Services from Rock Creek Facility (Hillsboro, OR) including two parallel trains: conventional A2O and Westbank configurations, allowing the model to be verified on conventional and side-stream EBPR systems as well.


Assuntos
Modelos Químicos , Fósforo/química , Poluentes Químicos da Água/análise , Biomassa , Reatores Biológicos , Desnitrificação , Glicogênio , Fósforo/análise , Polifosfatos
8.
Water Environ Res ; 89(11): 2043-2054, 2017 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-29080569

RESUMO

Enhanced biological phosphorus removal (EBPR) was observed in high-rate, non-nitrifying plants in the United States that were operated in a plug-flow mode. In facilities designed for nitrification and denitrification, a first-stage anaerobic zone, free of nitrate and nitrite was needed to accomplish EBPR, and this is referred to as the Phoredox (a.k.a. the AO and A2O) process. When a biological mechanism responsible for EBPR was proposed, these treatment configurations were accepted as normal practice, but many later observations showed that more reliable phosphorus removal could be achieved with alternative configurations. This paper discusses the development of alternative configurations for EBPR and the likelihood that a host of phosphate accumulating organisms (PAOs) that react to different environmental conditions might play a much bigger role in reliable and sustainable biological phosphorus removal. The conclusion is that conventional designs might have inadvertently selected for less efficient PAOs, while alternative configurations allowed for the growth of multiple PAO species such as Tetrasphaera, which can ferment higher carbon forms and take up phosphorus under anoxic conditions.


Assuntos
Reatores Biológicos , Fósforo/metabolismo , Anaerobiose , Biodegradação Ambiental , Fermentação , Fósforo/isolamento & purificação , Esgotos
9.
J Mater Chem B ; 12(18): 4489-4501, 2024 May 08.
Artigo em Inglês | MEDLINE | ID: mdl-38644661

RESUMO

Orthopedic device-related infection (ODRI) poses a significant threat to patients with titanium-based implants. The challenge lies in developing antibacterial surfaces that preserve the bulk mechanical properties of titanium implants while exhibiting characteristics similar to bone tissue. In response, we present a two-step approach: silver nanoparticle (AgNP) coating followed by selective laser-assisted surface alloying on commonly used titanium alumina vanadium (TiAl6V4) implant surfaces. This process imparts antibacterial properties without compromising the bulk mechanical characteristics of the titanium alloy. Systematic optimization of laser beam power (8-40 W) resulted in an optimized surface (32 W) with uniform TiAg alloy formation. This surface displayed a distinctive hierarchical mesoporous textured surface, featuring cauliflower-like nanostructures measuring between 5-10 nm uniformly covering spatial line periods of 25 µm while demonstrating homogenous elemental distribution of silver throughout the laser processed surface. The optimized laser processed surface exhibited prolonged superhydrophilicity (40 days) and antibacterial efficacy (12 days) against Staphylococcus aureus and Escherichia coli. Additionally, there was a significant twofold increase in bone mineralization compared to the pristine Ti6Al4V surface (p < 0.05). Rockwell hardness tests confirmed minimal (<1%) change in bulk mechanical properties compared to the pristine surface. This innovative laser-assisted approach, with its precisely tailored surface morphology, holds promise for providing enduring antibacterial and osteointegration properties, rendering it an optimal choice for modifying load-bearing implant devices without altering material bulk characteristics.


Assuntos
Ligas , Antibacterianos , Escherichia coli , Lasers , Próteses e Implantes , Prata , Staphylococcus aureus , Propriedades de Superfície , Titânio , Titânio/química , Titânio/farmacologia , Prata/química , Prata/farmacologia , Antibacterianos/farmacologia , Antibacterianos/química , Staphylococcus aureus/efeitos dos fármacos , Escherichia coli/efeitos dos fármacos , Ligas/química , Ligas/farmacologia , Animais , Testes de Sensibilidade Microbiana , Nanopartículas Metálicas/química , Calcificação Fisiológica/efeitos dos fármacos
10.
Water Res ; 251: 121050, 2024 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-38241807

RESUMO

While the adsorption/bio-oxidation (A/B) process has been widely studied for carbon capture and shortcut nitrogen (N) removal, its integration with enhanced biological phosphorus (P) removal (EBPR) has been considered challenging and thus unexplored. Here, full-scale pilot testing with an integrated system combining A-stage high-rate activated sludge with B-stage partial (de)nitrification/anammox and side-stream EBPR (HRAS-P(D)N/A-S2EBPR) was conducted treating real municipal wastewater. The results demonstrated that, despite the relatively low influent carbon load, the B-stage P(D)N-S2EBPR system could achieve effective P removal performance, with the carbon supplement and redirection of the A-stage sludge fermentate to the S2EBPR. The novel process configuration design enabled a system shift in carbon flux and distribution for efficient EBPR, and provided unique selective factors for ecological niche partitioning among different key functionally relevant microorganisms including polyphosphate accumulating organisms (PAOs) and glycogen-accumulating organisms (GAOs). The combined nitrite from B-stage to S2EBPR and aerobic-anoxic conditions in our HRAS-P(D)N/A-S2EBPR system promoted DPAOs for simultaneous internal carbon-driven denitrification via nitrite and P removal. 16S rRNA gene-based oligotyping analysis revealed high phylogenetic microdiversity within the Accumulibacter population and discovered coexistence of certain oligotypes of Accumulibacter and Competibacter correlated with efficient P removal. Single-cell Raman micro-spectroscopy-based phenotypic profiling showed high phenotypic microdiversity in the active PAO community and the involvement of unidentified PAOs and internal carbon-accumulating organisms that potentially played an important role in system performance. This is the first pilot study to demonstrate that the P(D)N-S2EBPR system could achieve shortcut N removal and influent carbon-independent EBPR simultaneously, and the results provided insights into the effects of incorporating S2EBPR into A/B process on metabolic activities, microbial ecology, and resulted system performance.


Assuntos
Esgotos , Purificação da Água , Desnitrificação , Fósforo/metabolismo , Rios , Nitrogênio , RNA Ribossômico 16S , Filogenia , Nitritos , Projetos Piloto , Reatores Biológicos , Purificação da Água/métodos , Polifosfatos/metabolismo , Carbono
11.
Sci Total Environ ; 857(Pt 1): 159280, 2023 Jan 20.
Artigo em Inglês | MEDLINE | ID: mdl-36216061

RESUMO

Water resource recovery facilities are faced with stringent effluent phosphorus limits to reduce nutrient pollution. Enhanced biological phosphorus removal (EBPR) is the most common biological route to remove phosphorus; however, many facilities struggle to achieve consistent performance due to limited carbon availability in the influent wastewater. A promising process to improve carbon availability is through return activated sludge (RAS) fermentation via sidestream EBPR (S2EBPR). In this study, a full-scale S2EBPR pilot was operated with a sidestream plus carbon configuration (SSRC) at a carbon-limited facility. A model based on the pilot test was developed and calibrated in the SUMO platform and used to explore routes for improving orthophosphate (OP) effluent compliance. Modeling results showed that RAS diversion by itself was not sufficient to drive OP removal to permit limits of 1 mg L-1, therefore, other strategies were evaluated. Supplemental carbon addition of MicroC® at 1.90 L min-1 and controlling the phosphorus concentration below 3.5 mgP L-1 in the primary effluent (PE) proved to be valid supplemental strategies to achieve OP removal below 1 mg L-1 most of the time. In particular, the proposed supplemental carbon flow rate would result in an improvement of the rbCOD:P ratio from 17:1 to 26:1. The synergistic approach of RAS diversion and supplemental carbon addition increased the polyphosphate accumulating organisms (PAO) population while minimizing the supplemental carbon needed to achieve consistent phosphorus removal. Overall, this pilot and modeling study shows that joint strategies, including RAS diversion, carbon addition and PE control, can be effective to achieve optimal control of OP effluent.


Assuntos
Fósforo , Águas Residuárias , Carbono , Reatores Biológicos , Esgotos
12.
Nanoscale Adv ; 5(21): 5850-5858, 2023 Oct 24.
Artigo em Inglês | MEDLINE | ID: mdl-37881699

RESUMO

In ferroelectric and multiferroic-based devices, it is often necessary to grow thicker films for enhanced properties. For certain phases that rely on substrate strain for growth, such thicker film growths beyond the typical thin film regime could be challenging. As an example, the Bi3Fe2Mn2Ox (BFMO) Aurivillius supercell (SC) phase possesses highly desirable multiferroic (i.e., ferromagnetic and ferroelectric) properties and a unique layered structure but relies heavily on substrate strain. Beyond the thin film regime (approximately 100 nm), a less desirable pseudo-cubic (PC) phase is formed. In this work, a novel heterogeneous re-seeding method is applied to maintain the strained growth in this SC phase beyond the thin film regime, thus enabling the growth of thick BFMO SC phase films. The insertion of periodic CeO2 interlayers reintroduces the heteroepitaxial strain and effectively re-initiates the growth of the SC phase. The thick BFMO SC phase maintains the overall multiferroic and interesting anisotropic optical properties, even exceeding those of the typical 100 nm SC film. This re-seeding method can be effectively adopted with other SC systems or strain-dependent thin films, thus introducing practical applications of the new SC phases without thickness limitations.

13.
Water Res ; 245: 120540, 2023 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-37688851

RESUMO

Side-stream enhanced biological phosphorus removal process (S2EBPR) has been demonstrated to improve performance stability and offers a suite of advantages compared to conventional EBPR design. Design and optimization of S2EBPR require modification of the current EBPR models that were not able to fully reflect the metabolic functions of and competition between the polyphosphate-accumulating organisms (PAOs) and glycogen-accumulating organisms (GAOs) under extended anaerobic conditions as in the S2EBPR conditions. In this study, we proposed and validated an improved model (iEBPR) for simulating PAO and GAO competition that incorporated heterogeneity and versatility in PAO sequential polymer usage, staged maintenance-decay, and glycolysis-TCA pathway shifts. The iEBPR model was first calibrated against bulk batch testing experiment data and proved to perform better than the previous EBPR model for predicting the soluble orthoP, ammonia, biomass glycogen, and PHA temporal profiles in a starvation batch testing under prolonged anaerobic conditions. We further validated the model with another independent set of anaerobic testing data that included high-resolution single-cell and specific population level intracellular polymer measurements acquired with single-cell Raman micro-spectroscopy technique. The model accurately predicted the temporal changes in the intracellular polymers at cellular and population levels within PAOs and GAOs, and further confirmed the proposed mechanism of sequential polymer utilization, and polymer availability-dependent and staged maintenance-decay in PAOs. These results indicate that under extended anaerobic phases as in S2EBPR, the PAOs may gain competitive advantages over GAOs due to the possession of multiple intracellular polymers and the adaptive switching of the anaerobic metabolic pathways that consequently lead to the later and slower decay in PAOs than GAOs. The iEBPR model can be applied to facilitate and optimize the design and operations of S2EBPR for more reliable nutrient removal and recovery from wastewater.

14.
Phys Rev Lett ; 109(24): 241801, 2012 Dec 14.
Artigo em Inglês | MEDLINE | ID: mdl-23368306

RESUMO

Natural models of supersymmetry with a gravitino lightest supersymmetric particle provide distinctive signatures at the LHC. For a neutralino next-to-lightest supersymmetric particle, sparticles can decay to two high energy photons plus missing energy. We use the ATLAS diphoton search with 4.8 b(-1) of data to place limits in both the top-squark-gluino and neutralino-chargino mass planes for this scenario. If the neutralino is heavier than 50 GeV, the lightest top squark must be heavier than 580 GeV, the gluino must be heavier than 1100 GeV, and charginos must be heavier than approximately 300-470 GeV. This provides the first nontrivial constraints in natural gauge mediation models with a neutralino next-to-lightest supersymmetric particle decaying to photons and implies a fine-tuning of at least a few percent in such models.

15.
Nanomaterials (Basel) ; 12(19)2022 Oct 03.
Artigo em Inglês | MEDLINE | ID: mdl-36234589

RESUMO

Nanocomposite thin film materials present great opportunities in coupling materials and functionalities in unique nanostructures including nanoparticles-in-matrix, vertically aligned nanocomposites (VANs), and nanolayers. Interestingly the nanocomposites processed through a non-equilibrium processing method, e.g., pulsed laser deposition (PLD), often possess unique metastable phases and microstructures that could not achieve using equilibrium techniques, and thus lead to novel physical properties. In this work, a unique three-phase system composed of BaTiO3 (BTO), with two immiscible metals, Au and Fe, is demonstrated. By adjusting the deposition laser frequency from 2 Hz to 10 Hz, the phase and morphology of Au and Fe nanoparticles in BTO matrix vary from separated Au and Fe nanoparticles to well-mixed Au-Fe alloy pillars. This is attributed to the non-equilibrium process of PLD and the limited diffusion under high laser frequency (e.g., 10 Hz). The magnetic and optical properties are effectively tuned based on the morphology variation. This work demonstrates the stabilization of non-equilibrium alloy structures in the VAN form and allows for the exploration of new non-equilibrium materials systems and their properties that could not be easily achieved through traditional equilibrium methods.

16.
Nanoscale Adv ; 5(1): 247-254, 2022 Dec 20.
Artigo em Inglês | MEDLINE | ID: mdl-36605792

RESUMO

Magnetoacoustic waves generated in piezoelectric and ferromagnetic coupled nanocomposite films through magnetically driven surface acoustic waves present great promise of loss-less data transmission. In this work, ferromagnetic metals of Ni, Co and Co x Ni1-x are coupled with a piezoelectric ZnO matrix in a vertically-aligned nanocomposite (VAN) thin film platform. Oxidation was found to occur in the cases of ZnO-Co, forming a ZnO-CoO VAN, while only very minor oxidation was found in the case of ZnO-Ni VAN. An alloy approach of Co x Ni1-x has been explored to overcome the oxidation during growth. Detailed microstructural analysis reveals limited oxidation of both metals and distinct phase separation between the ZnO and the metallic phases. Highly anisotropic properties including anisotropic ferromagnetic properties and hyperbolic dielectric functions are found in the ZnO-Ni and ZnO-Co x Ni1-x systems. The magnetic metal-ZnO-based hybrid metamaterials in this report present great potential in coupling of optical, magnetic, and piezoelectric properties towards future magnetoacoustic wave devices.

17.
Aorta (Stamford) ; 9(1): 35-37, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-34607383

RESUMO

Management of acute Type A aortic dissection can be complicated by patient comorbidities. We describe the case of a 29-year-old female with preexisting peripartum cardiomyopathy who developed a Type A dissection. Surgery was performed and venoarterial extracorporeal membrane oxygenation (ECMO) was instituted. She left hospital on the 71st postoperative day. It is extremely rare for a patient with cardiomyopathy to develop an aortic dissection. Deferring this patient's surgery to an ECMO center was crucial for her survival.

18.
J Pharm Sci ; 110(8): 2916-2924, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-33940028

RESUMO

Previously our laboratory first reported that dropping of freeze-dried monoclonal antibody (mAb) formulations could cause protein degradation and aggregation (J Pharm Sci, 2021, 1625). In this manuscript, we evaluated effects of secondary package on stability of several freeze-dried biopharmaceutical formulations during dropping. The degradation of mAb-Y during dropping with different secondary packages was determined by the sensitive particle analyzing techniques micro-flow imaging (MFI) and dynamic light scattering (DLS). Electron paramagnetic resonance (EPR) was used to detect free radicals after repeated dropping in different secondary packages. The amount of free radicals and SbVPs was correlated to the sample temperature as well as the secondary package during dropping. Our observations suggest that secondary packaging has significant effect on freeze-dried biopharmaceutical stability during dropping and therefore should be thoroughly screened and optimized to assure high product quality even for the presumed highly stable freeze-dried biopharmaceuticals.


Assuntos
Produtos Biológicos , Anticorpos Monoclonais , Embalagem de Medicamentos , Estabilidade de Medicamentos , Radicais Livres , Liofilização , Estabilidade Proteica
19.
Eur J Pharm Biopharm ; 149: 1-11, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32006605

RESUMO

We have observed an interesting phenomenon in which grinding of freeze-dried monoclonal antibody X (mAb-X) formulation powder resulted to significant protein sub-visible particles (SbVPs) in the reconstituted liquid, which could only be observed by sensitive particle analytical methods such as MFI and DLS. Effects of grinding temperature and the free radical scavengers methionine and 3-carbamoyl-2,2,5,5-tetramethyl-1-pyrrolidin-yloxy free radical (CTPO) on the formation of SbVPs were also evaluated. Free radicals were observed by EPR and the amount of free radicals was correlated to the sample temperature prior to grinding. Formation of SbVPs could be partially inhibited by methionine and CTPO. The amount of SbVPs formed was dependent on the amount of free radicals/sample temperature prior to grinding. At higher temperatures, more free radicals and SbVPs formed. Other than the previously known protein degradation due to high temperature formed during mechanical grinding, we propose an unreported and supplementary mechanism, i.e., the formation of free radicals (i.e., due to break of CO or CS bonds) in the dried state during mechanical grinding, leading to protein particle formation in the reconstituted solution. Our observation suggested that mechanical grinding of protein powder should be avoided or used cautiously (i.e., grinding temperature, strength and time) and the effects on radical and particle formation be fully evaluated.


Assuntos
Anticorpos Monoclonais/química , Química Farmacêutica , Radicais Livres/química , Proteínas/química , Óxidos N-Cíclicos/química , Sequestradores de Radicais Livres/química , Liofilização , Metionina/química , Pós , Temperatura
20.
Water Environ Res ; 92(3): 403-417, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31402530

RESUMO

Sidestream EBPR (S2EBPR) is an emerging alternative process to address common challenges in EBPR related to weak wastewater influent and may improve EBPR process stability. A systematic evaluation and comparison of the process performance and microbial community structure was conducted between conventional and S2EBPR facilities in North America. The statistical analysis suggested higher performance stability in S2EBPR than conventional EBPR, although possible bias associated with other plant-specific factors might have affected the comparison. Variations in stoichiometric values related to EBPR activity and discrepancies between the observed values and current model predictions suggested a varying degree of metabolic versatility of PAOs in S2EBPR systems that warrant further investigation. Microbial community analysis using various techniques suggested comparable known candidate PAO relative abundances in S2EBPR and conventional EBPR systems, whereas the relative abundance of known candidate GAOs seemed to be consistently lower in S2EBPR facilities than conventional EBPR facilities. 16S rRNA gene sequencing analysis revealed differences in the community phylogenetic fingerprints between S2EBPR and conventional facilities and indicated statistically higher microbial diversity index values in S2EBPR facilities than those in conventional EBPRs. PRACTITIONER POINTS: Sidestream EBPR (S2EBPR) can be implemented with varying and flexible configurations, and they offer advantages over conventional configurations for addressing the common challenges in EBPR related to weak wastewater influent and may improve EBPR process stability. Survey of S2EBPR plants in North America suggested statistically more stable phosphorus removal performance in S2EBPR plants than conventional EBPRs, although possible bias might affect the comparison due to other plant-specific factors. The EBPR kinetics and stoichiometry of the S2EBPR facilities seemed to vary and are associated with metabolic versatility of PAOs in S2EBPR systems that warrant further investigation. The abundance of known candidate PAOs in S2EBPR plants was similar to those in conventional EBPRs, and the abundance of known candidate GAOs was generally lower in S2EBPR than conventional EBPR facilities. Further finer-resolution analysis of PAOs and GAOs, as well as identification of other unknown PAOs and GAOs, is needed. Microbial diversity is higher in S2EBPR facilities compared with conventional ones, implying that S2EBPR microbial communities could show better resilience to perturbations due to potential functional redundancy.


Assuntos
Reatores Biológicos , Fósforo , Cinética , América do Norte , Filogenia , Polifosfatos , RNA Ribossômico 16S , Inquéritos e Questionários
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA