Cloning, characterization and functionality of the orotidine-5'-phosphate decarboxylase gene (URA3) of the glycolipid-producing yeast Candida bombicola

Candida bombicola is a yeast species known to synthesize glycolipids. Although these glycolipids find several industrial, cosmetic and pharmaceutical applications, very little is known about the genetics of C. bombicola. A basic tool for genetic study and modification is the availability of an efficient transformation and selection system. In order to develop such a system, the URA3 gene of Candida bombicola was isolated using degenerate PCR and genomic walking. The gene encodes for an enzyme of 262 amino acids and shows high homology with the known orotidine-5'-phosphate decarboxylases of several other yeast species. The functionality of the gene was proved by complementation of a URA3-negative Saccharomyces cerevisiae strain.     

Influence of Low-temperature Blanching Combined with High-pressure Shift Freezing on the Texture of Frozen Carrots

ABSTRACT: Freezing causes texture loss of tissue-based systems such as fruits and vegetables. To evaluate the potentials of high-pressure freezing for minimizing freezing damage, the effects of high-pressure shift freezing and regular freezing conditions on the texture of carrot cylinders were investigated. To improve the strength of the plant material by a pectin-based network, carrot cylinders were submitted to different pretreatment conditions before freezing. The reduced freezing time of high-pressure shift freezing compared with conventional freezing results in a limited positive effect on the hardness of non-pretreated carrots. A pronounced hardness improvement was obtained when calcium soaking followed by thermal (30 min at 60°C) or high-pressure (15 min at 60°C and 300 MPa) pretreatment was combined with high-pressure shift freezing. During subsequent frozen storage at -18°C, the increased hardness values of pretreated, high-pressure frozen carrots could not be maintained.     

Piece rates and their effects on health and safety - A literature review

The purpose of this study was to carry out a broad survey and analysis of relevant research articles about piece rate wages and their effects on health and safety that were published internationally until the fall of 2008. The aim was to summarize and describe the state of the art of the research in this field and if possible draw conclusions from the accumulated research results. A total of 75 research articles were examined extensively and 31 of these were found relevant and had sufficient quality to serve the purpose of this study. The findings of these relevant articles are summarized and analyzed in the survey. Since the late 1980s, there has been a change of research focus regarding piece rates and their effects on health and safety. More recent research shows a clear interest for health, musculoskeletal injuries, physical workload, pains and occupational injuries. The previous interest in risk behavior, security and accidents is still there, but no longer dominates the research scene.Although research is still sparse and fragmented, much of the accumulated knowledge about the effects of piece rate work tells us that piece rates in many situations have a negative effect on health and safety. The fact that 27 of the 31 studied articles found negative effects of piece rates on different aspects of health and safety does not prove causality, but together they give very strong support for the hypothesis that in most situations piece rates have negative effects on health and safety.In order to achieve better knowledge about the effects of piece rates in branches where piece rates are regarded problematic, further research is needed and such research has to be designed to meet the specific questions that are to be answered.     

Synthesis of Isobenzofuran Derivatives as heterocyclic analogues of the herbicide sindone B

The target compounds 21–27 were synthesized via bromination of the N,N,1,1-tetramethylisobenzofuranamines 13, 15 and 16 , subsequent bromine-lithium exchange and reaction with propanal or propanoyl chloride, respectively. In the course of some model reactions undertaken to test a synthetic strategy based on directed ortho-lithiation governed by the dimethylamino-group a useful synthesis of the ketone 3 was developed.     

A densely interconnected network for deep learning accelerated MRI

Objective

To improve accelerated MRI reconstruction through a densely connected cascading deep learning reconstruction framework.

Materials and methods

A cascading deep learning reconstruction framework (reference model) was modified by applying three architectural modifications: input-level dense connections between cascade inputs and outputs, an improved deep learning sub-network, and long-range skip-connections between subsequent deep learning networks. An ablation study was performed, where five model configurations were trained on the NYU fastMRI neuro dataset with an end-to-end scheme conjunct on four- and eightfold acceleration. The trained models were evaluated by comparing their respective structural similarity index measure (SSIM), normalized mean square error (NMSE), and peak signal to noise ratio (PSNR).

Results

The proposed densely interconnected residual cascading network (DIRCN), utilizing all three suggested modifications achieved a SSIM improvement of 8% and 11%, a NMSE improvement of 14% and 23%, and a PSNR improvement of 2% and 3% for four- and eightfold acceleration, respectively. In an ablation study, the individual architectural modifications all contributed to this improvement for both acceleration factors, by improving the SSIM, NMSE, and PSNR with approximately 2–4%, 4–9%, and 0.5–1%, respectively.

Conclusion

The proposed architectural modifications allow for simple adjustments on an already existing cascading framework to further improve the resulting reconstructions.