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1.
Adv Mater ; 34(35): e2203033, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-35790033

RESUMO

Anion-exchange-membrane water electrolyzers (AEMWEs) in principle operate without soluble electrolyte using earth-abundant catalysts and cell materials and thus lower the cost of green H2 . Current systems lack competitive performance and the durability needed for commercialization. One critical issue is a poor understanding of catalyst-specific degradation processes in the electrolyzer. While non-platinum-group-metal (non-PGM) oxygen-evolution catalysts show excellent performance and durability in strongly alkaline electrolyte, this has not transferred directly to pure-water AEMWEs. Here, AEMWEs with five non-PGM anode catalysts are built and the catalysts' structural stability and interactions with the alkaline ionomer are characterized during electrolyzer operation and post-mortem. The results show catalyst electrical conductivity is one key to obtaining high-performing systems and that many non-PGM catalysts restructure during operation. Dynamic Fe sites correlate with enhanced degradation rates, as does the addition of soluble Fe impurities. In contrast, electronically conductive Co3 O4 nanoparticles (without Fe in the crystal structure) yield AEMWEs from simple, standard preparation methods, with performance and stability comparable to IrO2 . These results reveal the fundamental dynamic catalytic processes resulting in AEMWE device failure under relevant conditions, demonstrate a viable non-PGM catalyst for AEMWE operation, and illustrate underlying design rules for engineering anode catalyst/ionomer layers with higher performance and durability.

2.
Springerplus ; 5(1): 1510, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27652083

RESUMO

BACKGROUND: Chinese Hamster Ovary (CHO) cells are the current industry standard for production of therapeutic monoclonal antibodies at commercial scales. Production optimisation in CHO cells hinges on analytical technologies such as the use of the polymerase chain reaction (PCR) to quantify genetic factors within the CHO genome and to detect the presence of contaminant organisms. PCR-based assays, whilst sensitive and accurate, are limited by (i) requiring lengthy sample preparation and (ii) a lack of standardisation. RESULTS: In this study we directly assess for the first time the effect of CHO cellular material on quantitative PCR (qPCR) and end-point PCR (e-pPCR) when used to measure and detect copies of a CHO genomic locus and a mycoplasma sequence. We also perform the first head-to-head comparison of the performance of a conventional qPCR method to that of the novel linear regression of efficiency (LRE) method when used to perform absolute qPCR on CHO-derived material. LRE qPCR features the putatively universal 'CAL1' standard. CONCLUSIONS: We find that sample preparation is required for accurate quantitation of a genomic target locus, but mycoplasma DNA sequences can be detected in the presence of high concentrations of CHO cellular material. The LRE qPCR method matches performance of a conventional qPCR approach and as such we invite the synthetic biology community to adopt CAL1 as a synthetic biology calibration standard for qPCR.

3.
J Man Manip Ther ; 22(4): 206-12, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25395829

RESUMO

OBJECTIVES: Cervical mobilization and manipulation have been shown to improve cervical range of motion and pain. Rotatory thrust manipulation applied to the lower cervical segments is associated with controversy and the potential for eliciting adverse reactions (AR). The purpose of this clinical trial was to describe two translatory non-thrust mobilization techniques and evaluate their effect on cervical pain, motion restriction, and whether any adverse effects were reported when applied to the C7 segment. METHODS: This trial included 30 participants with painful and restricted cervical rotation. Participants were randomly assigned to receive one of the two mobilization techniques. Active cervical rotation and pain intensity measurements were recorded pre- and post-intervention. Within group comparisons were determined using the Wilcoxon signed-rank test and between group comparisons were analyzed using the Mann-Whitney U test. Significance was set at P = 0.05. RESULTS: Thirty participants were evaluated immediately after one of the two mobilization techniques was applied. There was a statistically significant difference (improvement) for active cervical rotation after application of the C7 facet distraction technique for both right (P = 0.022) and left (P = 0.022) rotation. Statistically significant improvement was also found for the C7 facet gliding technique for both right (P = 0.022) and left rotation (P = 0.020). Pain reduction was statistically significant for both right and left rotation after application of both techniques. Both mobilization techniques produced similar positive effects and one was not statistically superior to the other. DISCUSSION: A single application of both C7 mobilization techniques improved active cervical rotation, reduced perceived pain, and did not produce any AR in 30 patients with neck pain and movement limitation. These two non-thrust techniques may offer clinicians an additional safe and effective manual intervention for patients with limited and painful cervical rotation. A more robust experimental design is recommended to further examine these and similar cervical translatory mobilization techniques.

4.
Kidney Int ; 68(1): 378-90, 2005 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-15954930

RESUMO

BACKGROUND: Nephrologists report that patients' choice should play an important role in the selection of renal replacement therapy (RRT) for end-stage renal disease (ESRD). In the United States, kidney transplant rates remain low and <10% of patients utilize home dialysis therapies. This study examined the effect of pre-ESRD processes on the selection of RRT among incident ESRD patients. METHODS: Using surveys, data were collected for all patients admitted to 229 dialysis units in ESRD Network 18 between April 1, 2002 and May 31, 2002. A total of 1365 patients began chronic dialysis and 1193 facility (87%) and 428 patient (31%) surveys were returned. RESULTS: Substantial proportions of patients were unaware of their kidney disease (36%) or were not seeing a nephrologist (36%) until <4 months before first dialysis. The presentation of treatment options was delayed (48% either after or < 1 month before the first dialysis). The majority of ESRD patients were not presented with chronic peritoneal dialysis, home hemodialysis, or renal transplantation as options (66%, 88%, and 74%, respectively). Using multivariate analyses, variables significantly associated with selection of chronic peritoneal dialysis as dialysis modality were the probability of chronic peritoneal dialysis being presented as a treatment option and the time spent on patient education. CONCLUSION: An incomplete presentation of treatment options is an important reason for under-utilization of home dialysis therapies and probably delays access to transplantation. Improvements in and reimbursement for pre-ESRD education could provide an equal and timely access for all medically suitable patients to various RRTs.


Assuntos
Acessibilidade aos Serviços de Saúde/estatística & dados numéricos , Falência Renal Crônica/psicologia , Falência Renal Crônica/terapia , Educação de Pacientes como Assunto/estatística & dados numéricos , Terapia de Substituição Renal/psicologia , Idoso , Coleta de Dados , Feminino , Hemodiálise no Domicílio/psicologia , Hemodiálise no Domicílio/estatística & dados numéricos , Humanos , Transplante de Rim/psicologia , Transplante de Rim/estatística & dados numéricos , Masculino , Pessoa de Meia-Idade , Nefrologia/estatística & dados numéricos , Satisfação do Paciente , Diálise Peritoneal/psicologia , Diálise Peritoneal/estatística & dados numéricos , Encaminhamento e Consulta/estatística & dados numéricos , Terapia de Substituição Renal/estatística & dados numéricos , Inquéritos e Questionários
5.
Nephrol News Issues ; 17(12): 30-6, 2003 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-14640008

RESUMO

ESRD Network 18 has identified numerous opportunities from improvement in the process of modality selection for incident patients commencing maintenance dialysis therapy. The overall goal for the Network is to ensure that all patients are presented with a choice for treatment in a timely manner. This in turn, would lead to better preparation of patients for RRT and hopefully, have a positive impact on the morbidity and mortality of maintenance dialysis patients.


Assuntos
Comportamento de Escolha , Falência Renal Crônica/terapia , Seleção de Pacientes , Terapia de Substituição Renal/métodos , Gestão da Qualidade Total/organização & administração , Coleta de Dados , Interpretação Estatística de Dados , Seguimentos , Humanos , Disseminação de Informação , Falência Renal Crônica/psicologia , Corpo Clínico/educação , Nefrologia/educação , Nefrologia/normas , Educação de Pacientes como Assunto , Participação do Paciente , Terapia de Substituição Renal/psicologia , Terapia de Substituição Renal/normas , Terapia de Substituição Renal/estatística & dados numéricos
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