261 research outputs found
Concept of Socio-Cyber-Physical Work Systems for Industry 4.0
In this paper the concepts of advanced production systems based on the challenges that bring the new industrial revolution named - Industry 4.0 are presented. The presented concept of socio-cyber-physical work systems is based on connecting social, cyber and physical working environments into a single functional, productive entity of the appointed elementary socio-cyber-physical work system.The elementary socio-cyber-physical work system is a basic building block of the cyber-physical production systems at the manufacturing level. The cyber system of the elementary socio-cyber-physical work system enables autonomous decision-making and cooperation in the network system. The possibility of implementing the proposed concept is based on the introduction of agency technologies in the domain of modern production systems and the development of information-communication technologies for the advanced management and control of cyber-physical production systems. Some illustrative examples reflect the experimental results of a research work in the field of cyber-physical systems and demonstrate the potential possibilities of implementing the concept of socio-cyber-physical work systems in the real industrial environment
Bioprocess Development for Lantibiotic Ruminococcin-A Production in Escherichia coli and Kinetic Insights Into LanM Enzymes Catalysis
Ruminococcin-A (RumA) is a peptide antibiotic with post-translational modifications including thioether cross-links formed from non-canonical amino acids, called lanthionines, synthesized by a dedicated lanthionine-generating enzyme RumM. RumA is naturally produced by Ruminococcus gnavus, which is part of the normal bacterial flora in the human gut. High activity of RumA against pathogenic Clostridia has been reported, thus allowing potential exploitation of RumA for clinical applications. However, purifying RumA from R. gnavus is challenging due to low production yields (120 mg Lâ1 for the chimeric construct and >150 mg Lâ1 for RumM. The correlation observed between microscale and lab-scale bioreactor cultivations suggests that the process is robust and realistically applicable to industrial-scale conditions.DFG, 53182490, EXC 314: Unifying Concepts in CatalysisDFG, 414044773, Open Access Publizieren 2019 - 2020 / Technische UniversitĂ€t Berli
Mapping Seyfert and LINER Excitation Modes in the Inner kpc of NGC 3393
We have mapped the extended narrow line region (ENLR) of NGC 3393 on scales
of (kpc) from the nucleus using emission
line images of H, [O III], and [S
II] taken with HST as part of the CHandra survey of
Extended Emission line Regions in nearby Seyfert galaxies (CHEERS). By mapping
these lines onto a spatially resolved Baldwin-Phillips-Terlevich (BPT) diagram,
we investigate the impact of feedback from a Compton-thick AGN on its
circumnuclear ISM. We find the expected Seyfert-like emission within the
ionization bicone (; 770 pc). We also find a new,
figure 8 shaped LINER cocoon enveloping the bicone and defining a sharp
(pc) transition between higher and lower ionization zones. These
data illustrate the morphological dependence of ionization states of the ENLR
relative to bicone and host gas geometries.Comment: Accepted by ApJ and published (2016, ApJ, 829, 46). Updated to
reflect the accepted versio
Evolution of the Quasar Luminosity Function Over 3 < z < 5 in the COSMOS Survey Field
We investigate the high-redshift quasar luminosity function (QLF) down to an
apparent magnitude of I(AB) = 25 in the Cosmic Evolution Survey (COSMOS).
Careful analysis of the extensive COSMOS photometry and imaging data allows us
to identify and remove stellar and low-redshift contaminants, enabling a
selection that is nearly complete for type-1 quasars at the redshifts of
interest. We find 155 likely quasars at z > 3.1, 39 of which have prior
spectroscopic confirmation. We present our sample in detail and use these
confirmed and likely quasars to compute the rest-frame UV QLF in the redshift
bins 3.1 < z < 3.5 and 3.5 < z < 5. The space density of faint quasars
decreases by roughly a factor of four from z \sim 3.2 to z \sim 4, with
faint-end slopes of {\beta} \sim -1.7 at both redshifts. The decline in space
density of faint optical quasars at z > 3 is similar to what has been found for
more luminous optical and X-ray quasars. We compare the rest-frame UV
luminosity functions found here with the X-ray luminosity function at z > 3,
and find that they evolve similarly between z \sim 3.2 and z \sim 4; however,
the different normalizations imply that roughly 75% of X-ray bright active
galactic nuclei (AGN) at z \sim 3 - 4 are optically obscured. This fraction is
higher than found at lower redshift and may imply that the obscured, type-2
fraction continues to increase with redshift at least to z \sim 4. Finally, the
implications of the results derived here for the contribution of quasars to
cosmic reionization are discussed.Comment: Accepted for publication in ApJ. 17 pages, 14 figure
Update on the current status of onchocerciasis in Cote dâIvoire following 40 years of intervention: Progress and challenges
Background
Onchocerciasis control in CĂŽte dâIvoire started with aerial insecticide spraying in 1974 and continued with community directed treatment with ivermectin (CDTi) from 1992 to the present. Onchocerciasis and lymphatic filariasis (LF) are co-endemic in 46 of the 81 health districts in the country. Fourteen and 12 districts are endemic for only LF or onchocerciasis, respectively. This paper aims to review the impact of past interventions on onchocerciasis in CĂŽte dâIvoire between 1975 and 2013, and review plans for disease elimination.
Methods
We reviewed microfilaria (MF, skin snip) prevalence and community microfilarial load (CMFL) data from published reports from 53 health districts during two major epidemiological assessment periods. Data from 1975 through 1991 provided information on the impact of vector control, and data from 1992 through 2016 provided information on the impact of CDTi.
Results
Weekly aerial insecticide spraying in 8 endemic districts between 1975 and 1991 reduced the overall MF prevalence by 68.1% from 43.5% to 13.9%. The CMFL also decreased in 7 out of 8 surveyed communities by 95.2% from 9.24 MF/snip to 0.44 MF/snip. Ivermectin distribution started in 1992. The coverage targets for control (65% of the total population) was reached in most endemic districts, and some areas achieved 80% coverage. Two sets of surveys were conducted to assess the impact of CDTi. Results from the first repeat surveys showed a significant decrease in overall MF prevalence (by 75.7%, from 41.6% to 10.1%). The second follow-up evaluation showed further improvement in most endemic districts and also documented major reductions in CMFL compared to baseline.
Conclusions
Extensive data collected over many years document the very significant impact of interventions conducted by the National Onchocerciasis and other Eyes Diseases Control Programme during challenging times with periods of civil unrest. The Health Ministry has now integrated efforts to control neglected tropical diseases and adopted the goal of onchocerciasis elimination
Large-scale implementation of disease control programmes: a cost-effectiveness analysis of long-lasting insecticide-treated bed net distribution channels in a malaria-endemic area of western Kenya-a study protocol.
Introduction
Historically, Kenya has used various distribution models for long-lasting insecticide-treated bed nets (LLINs) with variable results in population coverage. The models presently vary widely in scale, target population and strategy. There is limited information to determine the best combination of distribution models, which will lead to sustained high coverage and are operationally efficient and cost-effective. Standardised cost information is needed in combination with programme effectiveness estimates to judge the efficiency of LLIN distribution models and options for improvement in implementing malaria control programmes. The study aims to address the information gap, estimating distribution cost and the effectiveness of different LLIN distribution models, and comparing them in an economic evaluation.
Methods and analysis
Evaluation of cost and coverage will be determined for 5 different distribution models in Busia County, an area of perennial malaria transmission in western Kenya. Cost data will be collected retrospectively from health facilities, the Ministry of Health, donors and distributors. Programme-effectiveness data, defined as the number of people with access to an LLIN per 1000 population, will be collected through triangulation of data from a nationally representative, cross-sectional malaria survey, a cross-sectional survey administered to a subsample of beneficiaries in Busia County and LLIN distributorsâ records. Descriptive statistics and regression analysis will be used for the evaluation. A cost-effectiveness analysis will be performed from a health-systems perspective, and cost-effectiveness ratios will be calculated using bootstrapping techniques.
Ethics and dissemination
The study has been evaluated and approved by Kenya Medical Research Institute, Scientific and Ethical Review Unit (SERU number 2997). All participants will provide written informed consent. The findings of this economic evaluation will be disseminated through peer-reviewed publications
Heterologous biosynthesis, modifications and structural characterization of ruminococcin-A, a lanthipeptide from the gut bacterium ruminococcus gnavus E1, in escherichia coli
Ruminococcin A (RumA) is a lanthipeptide with high activity against pathogenic clostridia and is naturally produced by the strict anaerobic bacterium Ruminococcus gnavus E1, isolated from human intestine. Cultivating R. gnavus E1 is challenging, limiting high-quality production, further biotechnological development and therapeutic exploitation of RumA. To supply an alternative production system, the gene encoding RumA-modifying enzyme (RumM) and the gene encoding the unmodified precursor peptide (preRumA) were amplified from the chromosome of R. gnavus E1 and coexpressed in Escherichia coli. Our results show that the ruminococcin-A lanthionine synthetase RumM catalysed dehydration of threonine and serine residues and subsequently installed thioether bridges into the core structure of a mutant version of preRumA (preRumA*). These modifications were achieved when the peptide was expressed as a fusion protein together with GFP, demonstrating that a larger attachment to the N-terminus of the leader peptide does not obstruct in vivo processivity of RumM in modifying the core peptide. The leader peptide serves as a docking sequence which the modifying enzyme recognizes and interacts with, enabling its catalytic role. We further investigated RumM catalysis in conjunction with the formation of complexes observed between RumM and the chimeric GFP fusion protein. Results obtained suggested some insights into the catalytic mechanisms of class II lanthipeptide synthetases. Our data further indicated the presence of three thioether bridges, contradicting a previous report whose findings ruled out the possibility of forming a third ring in RumA. Modified preRumA* was activated in vitro by removing the leader peptide using trypsin and biological activity was achieved against Bacillus subtilis ATCC 6633. A production yield of 6 mg of pure modified preRumA* per litre of E. coli culture was attained and considering the size ratio of the leader-to-core segments of preRumA*, this amount would generate a final yield of approximately 1-2 mg of active RumA when the leader peptide is removed. The yield of our system exceeds that attainable in the natural producer by several thousand-fold. The system developed herein supplies useful tools for product optimization and for performing in vivo peptide engineering to generate new analogues with superior anti-infective properties.DFG, 325093850, Open Access Publizieren 2017 - 2018 / Technische UniversitÀt Berli
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