Student misconceptions are an obstacle in science, technology, engineering, and mathematics courses and unless remediated may continue causing difficulties in learning as students advance in their studies. Writing-to-learn assignments (WTL) are characterized by their ability to promote in-depth conceptual learning by allowing students to explore their understanding of a topic. This study sought to determine whether and what types of misconceptions are elicited by WTL assignments and how the process of peer review and revision leads to remediation or propagation of misconceptions. We examined four WTL assignments in an introductory biology course in which students first wrote about content by applying it to a realistic scenario, then participated in a peer-review process before revising their work. Misconceptions were identified in all four assignments, with the greatest number pertaining to protein structure and function. Additionally, in certain contexts, students used scientific terminology incorrectly. Analysis of the drafts and peer-review comments generated six profiles by which misconceptions were addressed through the peer-review process. The prevalent mode of remediation arose through directed peer-review comments followed by correction during revision. It was also observed that additional misconceptions were elicited as students revised their writing in response to general peer-review suggestions.

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Metabolic engineering has been developed for nearly 20 years since its beginning on 1990s, and it has significantly promoted the improvement of microbial fermentation industry. This review summarized the technology development and their applications in fermentation industry in each of the three important phases during the development of metabolic engineering. Finally, the key issues for future development and solving strategies were discussed.

Biotechnology techniques involving plant tissue culture and recombinant DNA technologies are powerful tools that can complement conventional breeding and expedite Capsicum improvement. The rate of progress in Capsicum is relatively slower than other members of Solanaceae because of its high genotypic dependence and recalcitrant nature. Capsicum is a recalcitrant plant in terms of in vitro cell, tissue and organ differentiation, plant regeneration and genetic transformation which makes it difficult to apply recombinant DNA technologies aimed at genetic improvement against pests, diseases and abiotic stress. Despite this, application of tissue culture and genetic transformation have led to significant development in chilli pepper plants, and studies are underway to achieve the targets of pre-harvest improvement and post-harvest characterization for value addition to this crop. This review presents a consolidated account of in vitro propagation and focuses upon contemporary information on biotechnological advances made in Capsicum.

The past several years have witnessed the evolution of gene medicine from an experimental technology into a viable strategy for developing therapeutics for a wide range of human disorders. Numerous prototype DNA-based biopharmaceuticals can now control disease progression by induction and/or inhibition of genes. These potent therapeutics include plasmids containing transgenes, oligonucleotides, aptamers, ribozymes, DNAzymes, and small interfering RNAs. Although only 2 DNA-based pharmaceuticals (an antisense oligonucleotide formulation, Vitravene, (USA, 1998), and an adenoviral gene therapy treatment, Gendicine (China, 2003), have received approval from regulatory agencies; numerous candidates are in advanced stages of human clinical trials. Selection of drugs on the basis of DNA sequence and structure has a reduced potential for toxicity, should result in fewer side effects, and therefore should eventually yield safer drugs than those currently available. These predictions are based on the high selectivity and specificity of such molecules for recognition of their molecular targets. However, poor cellular uptake and rapid in vivo degradation of DNA-based therapeutics necessitate the use of delivery systems to facilitate cellular internalization and preserve their activity. This review discusses the basis of structural design, mode of action, and applications of DNA-based therapeutics. The mechanisms of cellular uptake and intracellular trafficking of DNA-based therapeutics are examined, and the constraints these transport processes impose on the choice of delivery systems are summarized. Finally, the development of some of the most promising currently available DNA delivery platforms is discussed, and the merits and drawbacks of each approach are evaluated.

Human follicle-stimulating hormone (FSH) is now produced in vitro by recombinant DNA technology. FSH being a complex heterodimeric protein, a eukaryotic cell line has been selected for expression work (Chinese hamster ovary cells). The pharmaceutical preparation of recombinant human FSH (r-FSH) differs from that of human menopausal gonadotrophin (HMG) and the first generation of urinary human FSH (u-FSH) in terms of (i) source of bulk materials, (ii) purity and specific activity, (iii) batch to batch consistency, and (iv) complete absence of luteinizing hormone (LH) activity. Pharmacokinetic characterization of r-FSH has shown an absolute bioavailability of approximately 75% after both s.c. and i.m. administration and an apparent terminal half-life of 37 +/- 25 h. These characteristics are very similar to those of u-FSH. Clinical efficacy and safety are currently demonstrated through several randomized, well controlled studies, comparing r-FSH administered s.c. with u-FSH administered i.m. for stimulating follicular development prior to assisted reproduction treatment and in World Health Organization (WHO) group II anovulation. To date, approximately 1000 patients have been treated with r-FSH. Moreover, r-FSH has recently been used successfully in association with recombinant human LH for inducing ovulation and pregnancy in WHO group I anovulatory patients. At this stage of r-FSH preparation assessment, it is likely that r-FSH will replace all urinary-derived FSH preparations for stimulating ovarian follicular development. For clinicians, current experience with r-FSH indicates that it should be used with the regimes and doses applied to u-FSH.

In the post-genomic era, increasingly greater demands and expectations are being placed on protein production laboratories to produce more proteins and in faster timelines. This has been coupled with an exponential increase in the number of requests for the production of proteins which lack structural and functional information. No longer can groups use literature available in the public domain solely to drive their expression strategy, and moreover current expression and concomitant purification strategies clearly do not meet modern-day demands for protein production. This review will therefore attempt to provide a definitive review of current \'best in class\' cloning, expression and purification systems, and the adaptations and developments that have been made by laboratories, both academic and industrial, to enhance protein production throughput.

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