Expression of green fluorescent protein (GFPuv) in Escherichia coli DH5-a, under different growth conditions

The recombinant green fluorescent protein (GFPuv) was expressed by transformed cells of Escherichia coli DH5-α grown in LB/amp broth at 37oC, for 8 h and 24 h. To evaluate the effectiveness of different parameters to improve the expression of GFPuv by E. coli, four variable culturing conditions were set up for assays by a fractional factorial (24-1) design at two levels: (i) the effect of storing (24-48 h) the seeded broth at 4oC prior to incubation at 37oC; (ii) the effect of agitation speed (100-200 rpm); (iii) the final concentration (0.05-0.5 mM) of IPTG (isopropyl–β-D-thiogalactopyranoside); and (iv) the addition of IPTG at set cell densities (OD660 0.01-0.8). GFPuv was extracted from cells by the three phase partitioning method (TPP) and further purified with a methyl HIC column. The cultures grown at 37oC/24 h provided the highest yields of GFPuv under the conditions: (i) pre-storage at 4oC/24 h; (ii) agitation speed at 100 rpm; (iii) 0.5 mM IPTG; (iv) IPTG addition at OD660=~0.01. On the other hand, at 37oC/ 8 h, GFPuv expression was dependent upon agitation of broth cultures at 200 rpm and the IPTG addition at the beginning of the growth exponential phase. Key Words: Green fluorescent protein (GFPuv), Escherichia coli DH5-α, growth kinetic parameters, expressed GFPuv kinetic parameters, three phase partitioning extraction (TPP). African Journal of Biotechnology Vol.3(1) 2004: 105-11

Full Length Research Paper - Expression of green fluorescent protein (GFPuv) in Escherichia coli DH5-a, under different growth conditions

The recombinant green fluorescent protein (GFPuv) was expressed by transformed cells of Escherichia coli DH5-α grown in LB/amp broth at 37°C, for 8 h and 24 h. To evaluate the effectiveness of different parameters to improve the expression of GFPuv by E. coli, four variable culturing conditions were set up for assays by a fractional factorial (24-1) design at two levels: (i) the effect of storing (24-48 h) the seeded broth at 4°C prior to incubation at 37°C; (ii) the effect of agitation speed (100-200 rpm); (iii) the final concentration (0.05-0.5 mM) of IPTG (isopropyl-β-D-thiogalactopyranoside); and (iv) the addition of IPTG at set cell densities (OD660 0.01-0.8). GFPuv was extracted from cells by the three phase partitioning method (TPP) and further purified with a methyl HIC column. The cultures grown at 37°C/24 h provided the highest yields of GFPuv under the conditions: (i) pre-storage at 4°C/24 h; (ii) agitation speed at 100 rpm; (iii) 0.5 mM IPTG; (iv) IPTG addition at OD660=~0.01. On the other hand, at 37°C/ 8 h, GFPuv expression was dependent upon agitation of broth cultures at 200 rpm and the IPTG addition at the beginning of the growth exponential phase

Increase of nisin production by Lactococcus lactis in different media

Nisin production related to the growth conditions of Lactococcus lactis subsp. lactis   ATCC 11454, the effects of various media components and concomitant release of nisin into the media, were studied through transfers (five times). Nisin production was assayed by agar diffusion using Lactobacillus sake   ATCC 15521 as the sensitive test organism. The expression of nisin was strongly influenced by the addition of skimmed milk to both MRS and M17 broth, with the highest production obtained after the second and the fifth transfers, respectively, with maximum expression after 36 h of incubation

Work space II: attempts on Margarita

Margarita is a pile of constantly changing drafts ready to be revised, retold, forgotten, erased… Can we keep Margarita going? This performance installation asks for the audiences’ participation in constructing a collective consciousness: Margarita. It is created as part of Xristina’s Practice Research on performance design, and cognition at PCI using recordings, live performance and ‘scenographic contraptions’. The project contributed to the collection of qualitative data (images, post-show interviews, and participant questionnaires) for the analysis of the interaction between audience-participants, and the scenographic environment. Xristina is testing here a methodological tool brought into her research from her performance design and practice background: the contraption. She situates the metaphorical notion of consciousness as ‘multiple drafts’ following Dennett, who, when trying to explain how consciousness works ‘avoids supposing that there must be a single narrative (the “final” or “published” draft, you might say)’ (Dennett 1991: 113), but rather that there are multiple drafts or ‘narrative fragments’ at various stages of editing in various places in the brain (Dennett 1991: 113). This metaphor is used as a critical design-practice tool (contraption) for generating dynamic and reflective exchange between the audience-participants, the artists-collaborators, the environment and the practitioner-researcher. The audiences’ engagement and experience with this environment is further analysed using embodiment, the socially collaborative and ecological nature of human cognition.The composition of the work consists of pre-recorded voices of friends/colleagues/acquaintances of the practitioner-researcher and of live-streamed voices of random passers-by, answering the same set of questions regarding themselves or a female person they know well. The show is divided in 11 chapters, which correspond to the above questions and form a sonic collage, heard through a surround sound system controlled live by the sound designer, and the lighting designer. Container-structures invite the audience to literally immerse in them and listen to the more intimate audio recordings (i.e. the secret pleasures of Margarita). A folk English song talking about an apple and a head is performed live every 15 minutes, while multiple transcripts of the recordings are printed out ad hoc and placed on the floor for the audience to read; a button box waits to be explored and the lighting designer intervenes live corresponding with different lighting atmospheres. The audience-participants visiting the installation are invited to freely explore this sonic, performed and material environment and piece together the experience of Margarita.CePRA Revealing Practice bursar

Role of advanced simulation in undergraduate and postgraduate medical education

Medical simulations are effective education complements for medical training, demonstrating effective learning, level of participation, and improvement in knowledge, skills and attitudes. In undergraduate medical education, simulation provides the potential for valid, cost-benefit teaching and assessment of clinical skills, especially clinical reasoning skills, bridging the gap between theory and practice. Simulation as a training tool in postgraduate medical training is a practical method to provide a kind of educational realistic significance for practicing specialty in order to improve quality of care and patient safety. In particular, simulation is an excellent opportunity to implement reports of security which can be considered a true strategy in order to minimize clinical risk and ensure appropriate levels of quality in daily clinical practice

Data from: Estimating the reproducibility of psychological science

This record contains the underlying research data for the publication "Estimating the reproducibility of psychological science" and the full-text is available from: https://ink.library.smu.edu.sg/lkcsb_research/5257Reproducibility is a defining feature of science, but the extent to which it characterizes current research is unknown. We conducted replications of 100 experimental and correlational studies published in three psychology journals using high-powered designs and original materials when available. Replication effects were half the magnitude of original effects, representing a substantial decline. Ninety-seven percent of original studies had statistically significant results. Thirty-six percent of replications had statistically significant results; 47% of original effect sizes were in the 95% confidence interval of the replication effect size; 39% of effects were subjectively rated to have replicated the original result; and if no bias in original results is assumed, combining original and replication results left 68% with statistically significant effects. Correlational tests suggest that replication success was better predicted by the strength of original evidence than by characteristics of the original and replication teams