63 research outputs found
Protein refolding in an oscillatory flow reactor
We demonstrate that an oscillatory flow reactor is a viable reactor for protein refolding via direct dilution. The
mixing characteristics of the oscillatory flow reactor are well described and controllable and, importantly, can be
scaled-up to process scale without a loss of mixing efficiency. This makes the oscillatory flow reactor an attractive
alternative to conventional stirred-tank reactors for process-scale renaturation
Recommended from our members
The matching of a "one-dimensional" numerical simulation and experiment results for low viscosity Newtonian and non-Newtonian fluids during fast filament stretching and subsequent break-up
Molecular physics of a polymer engineering instability: Experiments and computation
Entangled polymer melts exhibit a variety of flow instabilities that limit production rates in industrial applications. We present both experimental and computational findings, using flow of monodisperse linear polystyrenes in a contraction-expansion geometry, which illustrate the formation and development of one such flow instability. This viscoelastic disturbance is observed at the slit outlet and subsequently produces large-scale fluid motions upstream. A numerical linear stability study using the molecular structure based Rolie-Poly model confirms the instability and identifies important parameters within the model, which gives physical insight into the underlying mechanism. Chain stretch was found to play a critical role in the instability mechanism, which partially explains the effectiveness of introducing a low-molecular weight tail into a polymer blend to increase its processability
Recommended from our members
The matching of polymer solution fast filament stretching, relaxation, and break up experimental results with 1D and 2D numerical viscoelastic simulation
this work was supported by EPSRC grant number RG5560
Homocysteine levels in preterm infants: is there an association with intraventricular hemorrhage? A prospective cohort study.
BACKGROUND: The purpose of this study was to characterize total homocysteine (tHcy) levels at birth in preterm and term infants and identify associations with intraventricular hemorrhage (IVH) and other neonatal outcomes such as mortality, sepsis, necrotizing enterocolitis, bronchopulmonary dysplasia, and thrombocytopenia. METHODS: 123 infants \u3c 32 weeks gestation admitted to our Level III nursery were enrolled. A group of 25 term infants were enrolled for comparison. Two blood spots collected on filter paper with admission blood drawing were analyzed by a high performance liquid chromatography (HPLC) method. Statistical analysis included ANOVA, Spearman\u27s Rank Order Correlation and Mann-Whitney U test. RESULTS: The median tHcy was 2.75 micromol/L with an interquartile range of 1.34 - 4.96 micromol/L. There was no difference between preterm and term tHcy (median 2.76, IQR 1.25 - 4.8 micromol/L vs median 2.54, IQR 1.55 - 7.85 micromol/L, p = 0.07). There was no statistically significant difference in tHcy in 31 preterm infants with IVH compared to infants without IVH (median 1.96, IQR 1.09 - 4.35 micromol/L vs median 2.96, IQR 1.51 - 4.84 micromol/L, p = 0.43). There was also no statistically significant difference in tHcy in 7 infants with periventricular leukomalacia (PVL) compared to infants without PVL (median 1.55, IQR 0.25 - 3.45 micromol/L vs median 2.85, IQR 1.34 - 4.82 micromol/L, p = 0.07). Male infants had lower tHcy compared to female; prenatal steroids were associated with a higher tHcy. CONCLUSION: In our population of preterm infants, there is no association between IVH and tHcy. Male gender, prenatal steroids and preeclampsia were associated with differences in tHcy levels
Quality of life among parents of preterm infants: a scoping review
Purpose: To synthesize the body of knowledge on the factors influencing the QoL of mothers and fathers of preterm infants.
Methods: A scoping review was performed. Publications indexed in PubMed®, Web of Science™, CINAHL® and PsycINFO® were searched, targeting studies presenting original empirical data that examined parental perception on QoL after a preterm delivery. Eligibility and data extraction were conducted by two independent researchers. The main quantitative findings were synthesized and qualitative data were explored by content analysis.
Results: The studies, 11 quantitative and 1 mixed methods, were derived mainly from the USA (n = 6). Heterogeneity across the studies was observed regarding the operationalization of QoL and the use of units of analysis (mothers, parents, families and caregivers). In a context where 40 out of 45 covariates were analysed by only one or two studies, results suggested that parental QoL after a preterm delivery is influenced by factors related with mother’s characteristics, family issues and health care environment rather than infants’ variables. Factors regarding fathers’ characteristics and structural levels were not addressed.
Conclusions: Standardizing the operationalization of the QoL when analysing mothers and fathers of preterm infants calls for a structured questionnaire adapted to their specific needs. Further research should include both mothers and fathers, invest in mixed methods approaches and be performed in different countries and settings for allowing integration and comparison of findings.This work was supported by FEDER funding from the Operational Programme Factors of Competitiveness—COMPETE and by national funding from the Foundation for Science and Technology—FCT (Portuguese Ministry of Science, Technology and Higher
Education) under the project “Parenting roles and knowledge in Neonatal Intensive Care Units” (FCOMP-01-0124-FEDER-019902; Ref. FCT PTDC/CS-ECS/120750/2010) and the Unidade de Investigação em Epidemiologia—Instituto de Saúde Pública da Universidade do Porto (EPIUnit) (POCI-01-0145-FEDER-006862; Ref. UID/DTP/04750/2013); the grants PD/BD/105830/2014 (to MA), SFRH/BPD/103562/2014 (to EA), co-funded by the FCT and the POPH/FSE Program and the FCT Investigator contract IF/01674/2015 (to SS)
- …