1,100 research outputs found

    Bioprospecting of yeasts for amylase production in solid state fermentation and evaluation of the catalytic properties of enzymatic extracts

    Get PDF
    Profiling microorganisms with potential for amylase production in low cost culture media has been widely recognized due to its broad applicability. The aim of this study was to select yeast strains with potential to produce amylolytic enzymes by solid state fermentation. Fifty-four (54) strains were assessed and three exhibited ability to produce amylases: Candida parapsilosis with 14.68 U/mL (146.8 U/g substrate); Rhodotorula mucilaginosa with 25.0 U/mL (250 U/g substrate), and Candida glabrata with 25.39 U/mL (253.9 U/g substrate), in solid state fermentation, for 120 h at 28°C, using wheat bran with 70% moisture. The enzymes exhibited maximum activity at a pH of 7.0 and at 60°C. Amylases demonstrated satisfactory structural stability, maintaining their catalytic activity after 1 h at 50°C. All enzymes were ethanol tolerant and retained more than 70% of their original activities in 15% ethanol solution. Corn starch was efficiently hydrolyzed by enzymes and the extracts produced by C. parapsilosis and C. glabrata exhibited dextrinizing activity, while those produced by R. mucilaginosa exhibited saccharifying activity. Key words: Candida parapsilosis, Candida glabrata, Rhodotorula mucilaginosa, dextrinizing and saccharifying activit

    Genome-wide signatures of complex introgression and adaptive evolution in the big cats.

    Get PDF
    The great cats of the genus Panthera comprise a recent radiation whose evolutionary history is poorly understood. Their rapid diversification poses challenges to resolving their phylogeny while offering opportunities to investigate the historical dynamics of adaptive divergence. We report the sequence, de novo assembly, and annotation of the jaguar (Panthera onca) genome, a novel genome sequence for the leopard (Panthera pardus), and comparative analyses encompassing all living Panthera species. Demographic reconstructions indicated that all of these species have experienced variable episodes of population decline during the Pleistocene, ultimately leading to small effective sizes in present-day genomes. We observed pervasive genealogical discordance across Panthera genomes, caused by both incomplete lineage sorting and complex patterns of historical interspecific hybridization. We identified multiple signatures of species-specific positive selection, affecting genes involved in craniofacial and limb development, protein metabolism, hypoxia, reproduction, pigmentation, and sensory perception. There was remarkable concordance in pathways enriched in genomic segments implicated in interspecies introgression and in positive selection, suggesting that these processes were connected. We tested this hypothesis by developing exome capture probes targeting ~19,000 Panthera genes and applying them to 30 wild-caught jaguars. We found at least two genes (DOCK3 and COL4A5, both related to optic nerve development) bearing significant signatures of interspecies introgression and within-species positive selection. These findings indicate that post-speciation admixture has contributed genetic material that facilitated the adaptive evolution of big cat lineages

    Jet production in charged current deep inelastic e⁺p scatteringat HERA

    Get PDF
    The production rates and substructure of jets have been studied in charged current deep inelastic e⁺p scattering for Q² > 200 GeV² with the ZEUS detector at HERA using an integrated luminosity of 110.5 pb⁻¹. Inclusive jet cross sections are presented for jets with transverse energies E_{T}^{jet} > 5 GeV. Measurements of the mean subjet multiplicity, 〈n_{sbj}〉, of the inclusive jet sample are presented. Predictions based on parton-shower Monte Carlo models and next-to-leading-order QCD calculations are compared to the measurements. The value of α_{s} (M_{z}), determined from 〈n_{sbj}〉 at y_{cut} = 10⁻² for jets with 25 < E_{T}^{jet} < 119 GeV, is α_{s} (M_{z}) = 0.1202 ± 0.0052 (stat.)_{-0.0019}^{+0.0060} (syst.)_{-0.0053}^{+0.0065} (th.). The mean subjet multiplicity as a function of Q² is found to be consistent with that measured in NC DIS

    High-level production of violacein by the newly isolated Duganella violaceinigra str. NI28 and its impact on Staphylococcus aureus

    Get PDF
    A violacein-producing bacterial strain was isolated and identified as a relative of Duganella violaceinigra YIM 31327 based upon phylogenetic analyses using the 16S rRNA, gyrB and vioA gene sequences and a fatty acid methyl ester (FAME) analysis. This new strain was designated D. violaceinigra str. NI28. Although these two strains appear related based upon these analyses, the new isolate was phenotypically different from the type strain as it grew 25% faster on nutrient media and produced 45-fold more violacein. When compared with several other violacein producing strains, including Janthinobacterium lividum, D. violaceinigra str. NI28 was the best violacein producer. For instance, the crude violacein yield with D. violaceinigra str. NI28 was 6.0 mg/OD at 24 hours, a value that was more than two-fold higher than all the other strains. Finally, the antibacterial activity of D. violaceinigra str. NI28 crude violacein was assayed using several multidrug resistant Staphylococcus aureus. Addition of 30 mu M crude violacein led to a 96% loss in the initial S. aureus population while the minimum inhibitory concentration was 1.8 mu M. Consequently, this novel isolate represents a phenotypic variant of D. violaceinigra capable of producing much greater quantities of crude violacein, an antibiotic effective against multidrug resistant S. aureusopen

    Evaluation of a joint Bioinformatics and Medical Informatics international course in Peru

    Get PDF
    Background: New technologies that emerge at the interface of computational and biomedical science could drive new advances in global health, therefore more training in technology is needed among health care workers. To assess the potential for informatics training using an approach designed to foster interaction at this interface, the University of Washington and the Universidad Peruana Cayetano Heredia developed and assessed a one-week course that included a new Bioinformatics (BIO) track along with an established Medical/Public Health Informatics track (MI) for participants in Peru. Methods: We assessed the background of the participants, and measured the knowledge gained by track-specific (MI or BIO) 30-minute pre- and post-tests. Participants' attitudes were evaluated both by daily evaluations and by an end-course evaluation. Results: Forty-three participants enrolled in the course - 20 in the MI track and 23 in the BIO track. Of 20 questions, the mean % score for the MI track increased from 49.7 pre-test (standard deviation or SD = 17.0) to 59.7 (SD = 15.2) for the post-test (P = 0.002, n = 18). The BIO track mean score increased from 33.6 pre-test to 51.2 post-test (P less than 0.001, n = 21). Most comments (76%) about any aspect of the course were positive. The main perceived strength of the course was the quality of the speakers, and the main perceived weakness was the short duration of the course. Overall, the course acceptability was very good to excellent with a rating of 4.1 (scale 1-5), and the usefulness of the course was rated as very good. Most participants (62.9%) expressed a positive opinion about having had the BIO and MI tracks come together for some of the lectures. Conclusion: Pre- and post-test results and the positive evaluations by the participants indicate that this first joint Bioinformatics and Medical/Public Health Informatics (MI and BIO) course was a success.The University of Washington AMAUTA Global Training in Health Informatics, a Fogarty International Center/NIH funded grant (5D43TW007551), and the AMAUTA Research Practica Program, a Puget Sound Partners for Global Health-funded grant

    Modeling ophthalmic surfaces using Zernike, Bessel and Chebyshev type functions

    Get PDF
    The visual system of the human eye is a part of the central nervous system by which the human body sees and interprets the information provided by the visible light in order to build a representation of the world around. During the propagations of the light through the eye, the retinal image can be deteriorated by diseases and disorders. For retinal images, the most important sources of images quality degradation are diffraction and optical aberrations. In order to measure and correct aberrations, there is a number of surfaces related to the anatomy and physiology of the eye. It is important to measure and mathematically model these surfaces to study their properties.publishe

    Validity of the disabilities of the Arm, Shoulder and Hand patient-reported outcome measure (DASH) and the Quickdash when used in Dupuytren’s disease

    Get PDF
    This study investigated aspects of the validity and reliability of the 30-item Disabilities of the Arm, Shoulder and Hand patient-reported outcome measure (DASH) and its relationship with the shorter 11-item QuickDASH in patients with Dupuytren’s disease. Seven hundred and fifty-nine DASH questionnaires were studied, covering pre- and postoperative patients undergoing different treatments for Dupuytren’s disease. Items related to pain rose early after treatment before returning to baseline, suggesting that studying pain is relevant during postoperative recovery. Across all 759 sets of responses, the QuickDASH agreed closely with the DASH. In exploratory factor analysis, the DASH was not unidimensional, questioning the validity of the DASH summary score in Dupuytren’s disease. Further validation of existing PROMs for use in Dupuytren’s disease is needed. These data suggest that pain is a relevant symptom to study during postoperative recovery following treatment for Dupuytren’s disease
    corecore