Model System For Production Research Articles

Contributions of Yersinia pestis outer membrane protein Ail to plague pathogenesis.

Pathogenic Yersinia have been a productive model system for studying bacterial pathogenesis. Hallmark contributions of Yersinia research to medical microbiology are legion and include: (i) the first identification of the role of plasmids in virulence, (ii) the important mechanism of iron acquisition from the host, (iii) the first identification of bacterial surface proteins required for host cell invasion, (iv) the archetypical type III secretion system, and (v) elucidation of the role of genomic reduction in the evolutionary trajectory from a fairly innocuous pathogen to a highly virulent species. The outer membrane (OM) protein Ail (attachment invasion locus) was identified over 30 years ago as an invasin-like protein. Recent work on Ail continues to provide insights into Gram-negative pathogenesis. This review is a synopsis of the role of Ail in invasion, serum resistance, OM stability, thermosensing, and vaccine development. Ail is shown to be an essential virulence factor with multiple roles in pathogenesis. The recent adaptation of Yersinia pestis to high virulence, which included genomic reduction to eliminate redundant protein functions, is a model to understand the emergence of new bacterial pathogens.

Mathematical modeling of the technological process and synthesis of the amidation control system

There is still no exact mathematical model or control system for sodium sulphacyl production, so not all available control systems are accurate and not all possible disturbances of the system during operation have been identified. An urgent problem is to create an optimal mathematical model and use it as the basis for the synthesis of an amidator control system using a controller.
 In creating a mathematical model for the synthesis of the control system for the amidation process, it is necessary to understand the component of its mechanism. The amidation reaction takes place with a significant heat release, as well as through the available catalyst in the amidator, and side reactions occur. Using static and dynamic characteristics, a mathematical model was created, from which a control system was developed using a PID controller. 
 After a mathematical model has been developed, it becomes clear that the amidator must be cooled constantly for its correct operation, because the lower the temperature of the amide at the outlet, the better the product. The temperature must be maintained at a level of 324K to 327K with water supply for cooling at 19-20 kg/s. The implemented automatic process control allows the production capacity to be managed at minimal cost. The PID controller, which is configured according to the formula of the transfer function of the amidator and the transport delay link, was selected as the main controller. The controller used includes two components: integral and differential.
 The synthesis of the control system based on the PID controller made it possible to fully investigate the process taking into account the disturbances, which were still uncertain, increased the rate of reaching a steady level, and reduced production costs.

Phase behavior of the oleic acid – methanol – methyl oleate – water mixture as a promising model system for biodiesel production: Brief data review and new results at 303.15 K and atmospheric pressure

The objective of this study is the investigation of solubility, critical states and liquid-liquid equilibrium of the quaternary system oleic acid – methanol – methyl oleate – water and its ternary and binary subsystems at 303.15 K and atmospheric pressure. A brief review of the literature on the studied system is presented. The compositions for binodal curves and for surface of solubility were determined using cloud-point technique. Tie-lines of liquid–liquid equilibrium were obtained using NMR spectroscopy. Experimental results were represented by diagrams in concentration simplices including 3D phase diagram in composition tetrahedron. A comparative analysis with the available literature data has been carried out. Correlation and prediction of experimental LLE data was performed using NRTL and UNIFAC models, respectively. Results of modeling was found to has a satisfactory agreement with the experimental data.

A research on integrated district energy system planning considering hydrogen production

In this paper, the comprehensive energy system of wind power hydrogen production plant is considered. Firstly, wind power hydrogen production model, electrolysis hydrogen production model and comprehensive energy system model containing wind power hydrogen production are proposed, combining the operation model in the comprehensive energy system, electric heating load demand and the operation characteristics of the power system. Secondly, the objective function of the integrated energy system is to optimize for the lowest total operating cost, establish an optimization model, and restrict its overall power balance and the relevant constraints of each part. Finally, energyplan is adopted for simulation operation. The results show that the integrated energy system considering wind power for hydrogen production can better absorb wind energy, reduce the phenomenon of wind abandonment, and convert wind abandonment into hydrogen resources, which can improve economic benefits and make full use of energy.

Proton-assisted electron transfer and hydrogen-atom diffusion in a model system for photocatalytic hydrogen production

Solar energy can be converted into chemical energy by photocatalytic water splitting to produce molecular hydrogen. Details of the photo-induced reaction mechanism occurring on the surface of a semiconductor are not fully understood, however. Herein, we employ a model photocatalytic system consisting of single atoms deposited on quantum dots that are anchored on to a primary photocatalyst to explore fundamental aspects of photolytic hydrogen generation. Single platinum atoms (Pt1) are anchored onto carbon nitride quantum dots (CNQDs), which are loaded onto graphitic carbon nitride nanosheets (CNS), forming a Pt1@CNQDs/CNS composite. Pt1@CNQDs/CNS provides a well-defined photocatalytic system in which the electron and proton transfer processes that lead to the formation of hydrogen gas can be investigated. Results suggest that hydrogen bonding between hydrophilic surface groups of the CNQDs and interfacial water molecules facilitates both proton-assisted electron transfer and sorption/desorption pathways. Surface bound hydrogen atoms appear to diffuse from CNQDs surface sites to the deposited Pt1 catalytic sites leading to higher hydrogen-atom fugacity surrounding each isolated Pt1 site. We identify a pathway that allows for hydrogen-atom recombination into molecular hydrogen and eventually to hydrogen bubble evolution.

Change management practices to support the implementation of lean production systems: a survey of the scientific literature

Abstract: The transition from mass production system to lean production system carrier significant changes in operational strategies of industrial organizations. A production model system can engender different reactions by the people involved; some of them can show resistance during the process, ranging from unreserved support to a hidden resistance (even explicit). In order to identify the main practices to support change processes, this study provides a literature review to systematize the main researches related to change management during lean manufacturing implementation. This study aims to provide a systematic literature review covering main researches related to change management and lean manufacturing implementation to identify the main factors that affect the production system change. The research was carried out between October 2016 and January 2018. In methodological terms, literature review was developed by using Scopus and ISI web of Science publications. As a result of this study, 25 papers related to lean manufacturing implementation were identified and 10 factors were consolidated. The most relevant practices of change management were also identified to support lean production system implementation.

Discriminating changes in intracellular NADH/NAD+ levels due to anoxicity and H2 supply in R. eutropha cells using the Frex fluorescence sensor

The hydrogen-oxidizing “Knallgas” bacterium Ralstonia eutropha can thrive in aerobic and anaerobic environments and readily switches between heterotrophic and autotrophic metabolism, making it an attractive host for biotechnological applications including the sustainable H2-driven production of hydrocarbons. The soluble hydrogenase (SH), one out of four different [NiFe]-hydrogenases in R. eutropha, mediates H2 oxidation even in the presence of O2, thus providing an ideal model system for biological hydrogen production and utilization. The SH reversibly couples H2 oxidation with the reduction of NAD+ to NADH, thereby enabling the sustainable regeneration of this biotechnologically important nicotinamide cofactor. Thus, understanding the interaction of the SH with the cellular NADH/NAD+ pool is of high interest. Here, we applied the fluorescent biosensor Frex to measure changes in cytoplasmic [NADH] in R. eutropha cells under different gas supply conditions. The results show that Frex is well-suited to distinguish SH-mediated changes in the cytoplasmic redox status from effects of general anaerobiosis of the respiratory chain. Upon H2 supply, the Frex reporter reveals a robust fluorescence response and allows for monitoring rapid changes in cellular [NADH]. Compared to the Peredox fluorescence reporter, Frex displays a diminished NADH affinity, which prevents the saturation of the sensor under typical bacterial [NADH] levels. Thus, Frex is a valuable reporter for on-line monitoring of the [NADH]/[NAD+] redox state in living cells of R. eutropha and other proteobacteria. Based on these results, strategies for a rational optimization of fluorescent NADH sensors are discussed.

Towards Model-based Process Engineering

AbstractThe high interaction between process and product models in product development and systems engineering (SE) is common sense. However, most research in the field of model based systems engineering (MBSE) focusses of physical systems (hardware and software). The authors claim that this focus is a main reason for the low acceptance and high effort for implementation of SE and MBSE in industrial practice. Thus, this contribution aims at supporting an integrative analysis and synthesis of process and product models by introducing the concept and framework of Model-based Process Engineering. Based on established research this framework introduces three main systems, namely the system of processes, system of product models, and system of tools to describe complex product development. The main contribution of this work is a preliminary concept to structure and link the systems of processes and product models. Besides form the description of the main relations between the systems an integrated modelling concept to represent links between the process and product model system is proposed.

The development of an alternative fermentation model system for vinegar production

This study was conducted to develop and optimise an alternative fermentation model system using mushrooms (Pleurotus pulmonarius and Volvariella volvacea) and yeast (Saccharomyces cerevisiae) as the starter cultures, while standard glucose solution was used as the substrate for fermentation. The optimisation was performed on two factors, fermentation time and culture ratio, using D-optimal mixture design. Both fermentation time and culture ratio showed significant (p < 0.05) effects on reducing sugar content and increasing the ethanol content for alcoholic fermentation. The optimum fermentation conditions were 72 h of fermentation and using a S. cerevisiae:P. pulmonarius mycelia:V. volvacea mycelia culture ratio of 1:1:1, achieving a desirability of 0.901. A verification test was performed, and there was no significant difference (p > 0.05) in the ethanol content between the experimental value (13.45 ± 0.99%) and the predicted value (13.52%). Vinegar production was carried out using the optimised alcoholic sample through the inoculation of mother of vinegar and Kombucha. The concentrations of acetic acid from both samples of vinegar were between 2.05% and 2.41% with zero residual ethanol. In conclusion, an alternative fermentation model system for vinegar production using mushrooms and yeast, followed by mother of vinegar and Kombucha inoculation, has been successfully developed with the desired physiochemical properties.

A model system for off season cherry production in northern China

A model system for off season cherry production in northern China

Evaluating Labor Productivity in a Plant Production System with Sole-source Lighting: A Case Study

Labor productivity in terms of material value (weight of plants harvested per hour per person) was evaluated for 6 months from the start of operations in a research facility at Osaka Prefecture University (Osaka, Japan), serving as a model system for plant production with sole-source lighting (also referred to as a “vertical farm” or “plant factory”). The research facility is capable of producing lettuce plants (Lactuca sativa) at a maximum production rate of ≈5000 plants/day when the relative harvest rate (i.e., number of plants harvested/maximum potential number of plants harvested) is 100%. However, in the present study, the relative harvest rate at the research facility was in the range of 17% to 65% and labor productivity varied from 1.5 to 6.0 kg·h−1 per person. The evaluation results indicated that increasing the weight of plants harvested and increasing the relative harvest rate was necessary to maintain a high level of labor productivity. The processing time for harvesting was greatest among all plant operations, suggesting the need to reduce the time taken in this operation to increase the labor productivity in the research facility and in other plant production systems with sole-source lighting (PPSLs). This study demonstrates the importance of analyzing labor productivity for increasing the commercial feasibility of PPSLs. However, further long-term investigation with higher relative harvest rates is required for a more definitive conclusion.

Intermolecular RNA Recombination Occurs at Different Frequencies in Alternate Forms of Brome Mosaic Virus RNA Replication Compartments.

Positive-strand RNA viruses replicate their genomes in membrane-bound replication compartments. Brome mosaic virus (BMV) replicates in vesicular invaginations of the endoplasmic reticulum membrane. BMV has served as a productive model system to study processes like virus-host interactions, RNA replication and recombination. Here we present multiple lines of evidence showing that the structure of the viral RNA replication compartments plays a fundamental role and that recruitment of parental RNAs to a common replication compartment is a limiting step in intermolecular RNA recombination. We show that a previously defined requirement for an RNA recruitment element on both parental RNAs is not to function as a preferred crossover site, but in order for individual RNAs to be recruited into the replication compartments. Moreover, modulating the form of the replication compartments from spherular vesicles (spherules) to more expansive membrane layers increased intermolecular RNA recombination frequency by 200- to 1000-fold. We propose that intermolecular RNA recombination requires parental RNAs to be recruited into replication compartments as monomers, and that recruitment of multiple RNAs into a contiguous space is much more common for layers than for spherules. These results could explain differences in recombination frequencies between viruses that replicate in association with smaller spherules versus larger double-membrane vesicles and convoluted membranes.

Modelling flood reservoir integrated with pumped hydropower storage for electricity production using HOMER

This paper presented the potential of flood reservoir integrated with pumped hydropower storage for electricity production in Pekan, Malaysia. Based on the procedure in T echnical Release 55 (T R- 55), the volume of the reservoir to attenuat e flood was 5.2 million3. The volume estimated will be the size of the lower reservoir of proposed PHS and act as flood water catchment during flood seasons. The system proposed an integration of PHS with wind turbines and connect it to the grid. The Hybrid Optimization Model for Electric Renewable (HOMER) software was used to model system for electricity production. The software has simulated 200 different configurations of systems which included the diesel-only system and hybrid wind/diesel system. The standalone diesel system could produce about 25,041,824 kWh of electricity per year and emits 30,030,457 kg/year of pollutants into the atmosphere. Meanwhile, the hybrid wind/diesel could produce 25,668,980 kWh/year of electricity and emits 29,293,174 kg/year of total pollutants into the air. Although, the standalone diesel has the lowest cost of energy among all configurations which is RM 0.852/kWh, but it releases the most amount of carbon dioxide. The high emission of this gasses can have many environmental effect s in a long term.

Quantifying syringeal dynamics in vitro using electroglottography.

The complex and elaborate vocalizations uttered by many of the 10,000 extant bird species are considered a major driver in their evolutionary success, warranting study of the underlying mechanisms of vocal production. Additionally, birdsong has developed into a highly productive model system for vocal imitation learning and motor control, where, in contrast to humans, we have experimental access to the entire neuromechanical control loop. In human voice production, complex laryngeal geometry, vocal fold tissue properties, airflow and laryngeal musculature all interact to ultimately control vocal fold kinematics. Quantifying vocal fold kinematics is thus critical to understanding neuromechanical control of voiced sound production, but in vivo imaging of vocal fold kinematics in birds is experimentally challenging. Here, we adapted and tested electroglottography (EGG) as a novel tool for examining vocal fold kinematics in the avian vocal organ, the syrinx. We furthermore imaged and quantified syringeal kinematics in the pigeon (Columba livia) syrinx with unprecedented detail. Our results show that EGG signals predict (1) the relative amount of contact between the avian equivalent of vocal folds and (2) essential parameters describing vibratory kinematics, such as fundamental frequency, and timing of syringeal opening and closing events. As such, EGG provides novel opportunities for measuring syringeal vibratory kinematic parameters in vivo Furthermore, the opportunity for imaging syringeal vibratory kinematics from multiple planar views (horizontal and coronal) simultaneously promotes birds as an excellent model system for studying kinematics and control of voiced sound production in general, including in humans and other mammals.

Environmental assessment of bioproducts in development stage: The case of fiberboards made from coconut residues

Fiberboards made from agro-industrial residues have been developed recently to add value to residues and decrease demand for wood and its byproducts. Nonetheless, new bioproducts made from residues are not inherently beneficial to the environment and bring no guarantee of improved efficiency in the use of resources, when compared to standard products. The impacts of these new bioproducts shall be compared to standard products to foster improvements and reduce potential harms to the environment from the development stage. This study assesses the environmental impacts of new coconut husk-based fiberboards, at development stage, aiming to prioritize those for future improvements and up-scaling. The following fiberboards are analyzed: i) MDF made exclusively of coir and fiber; ii) MDF UF made of coir and fiber bonded with urea-formaldehyde; and iii) HDF made only of coir and fiber. This assessment is performed considering different scenarios for allocation procedures (mass and economic, for current and future husk market value) and production scales (lab and pilot). The up-scaled husk-based fiberboards are compared to commercial wood-based panels to support decision about which products should be further improved. Short and long-term research agendas are proposed for reducing the potential impacts of these new products. This cradle to gate study is based on the ISO 14040 and 14044 standards for life cycle assessment, considering the production of fiberboards with 6.05*10−5 m3, at laboratory scale, and 1 m3, at pilot scale. The results show that husk-based MDF and HDF have high potential in terms of environmental performance. Nonetheless, they still require improvements to better compete with wood-based fiberboards when mass allocation is the criteria applied in the product modelling system. The hotspot analysis of MDF and HDF highlights the need to reduce impacts in husk transportation and processing, as well as in coconut farming. Two research agendas are proposed to improve MDF and HDF environmental performances: i) a short-term agenda, focused on reducing transportation distances and reusing nutrient rich effluents from husk processing in crop irrigation; and ii) a long-term agenda, focused on reducing the dependence of coconut farming in commercial fertilizers and improving the efficiency of irrigation. From this environmental assessment, the importance of applying both mass and economic allocation in the study of new bio-based products is shown. Furthermore, the need to design and evaluate up-scaled processes, at laboratory stage, in order to make meaningful choices among products is also highlighted. The methodological framework adopted in this study may support research teams searching to improve the environmental performance of products from laboratory stage.

The Effects of Pitch Shifts on Delay-Induced Changes in Vocal Sequencing in a Songbird.

Like human speech, vocal behavior in songbirds depends critically on auditory feedback. In both humans and songbirds, vocal skills are acquired by a process of imitation whereby current vocal production is compared to an acoustic target. Similarly, performance in adulthood relies strongly on auditory feedback, and online manipulations of auditory signals can dramatically alter acoustic production even after vocalizations have been well learned. Artificially delaying auditory feedback can disrupt both speech and birdsong, and internal delays in auditory feedback have been hypothesized as a cause of vocal dysfluency in persons who stutter. Furthermore, in both song and speech, online shifts of the pitch (fundamental frequency) of auditory feedback lead to compensatory changes in vocal pitch for small perturbations, but larger pitch shifts produce smaller changes in vocal output. Intriguingly, large pitch shifts can partially restore normal speech in some dysfluent speakers, suggesting that the effects of auditory feedback delays might be ameliorated by online pitch manipulations. Although birdsong provides a promising model system for understanding speech production, the interactions between sensory feedback delays and pitch shifts have not yet been assessed in songbirds. To investigate this, we asked whether the addition of a pitch shift modulates delay-induced changes in Bengalese finch song, hypothesizing that pitch shifts would reduce the effects of feedback delays. Compared with the effects of delays alone, combined delays and pitch shifts resulted in a significant reduction in behavioral changes in one type of sequencing (branch points) but not another (distribution of repeated syllables).

Co-cultivation of Chlorella spp and tomato in a hydroponic system

In this study, a new cost-effective and environmentally sustainable microalgal production strategy was developed on the basis of the microalgae-crop symbiosis association. This method allowed the simultaneous production of microalgae and crops by using a simple eco-hydroponic system (EHS), with the input only for crop production. In glasshouse experiments, green algae Chlorella infusionum was successfully cultivated in a hydroponic culture system cultivating tomato. The algal and crop biomass productivities in the EHS were 32 ± 5 g m−3 d−1 and 54.24 ± 1.81 g dm−3 d−1 (n = 6 for each), respectively, which was significantly (P < 0.05) greater than the algal biomass productivity (16 ± 5 g m−3 d−1, n = 6) in the algal monoculture and the crop biomass productivity (33.97 ± 7.58 g dm−3 d−1, n = 6) in the crop monoculture without aeration. The enhancement of the biomass productions was mainly attributed to the aeration from algal photosynthesis and the CO2 fertilization from crop root respiration in the EHS. Particularly, the nitrogen and phosphorus utilization efficiencies were high due to co-utilization of the nutrients by microalgae and crop in the EHS. This simple system could thus be applied as a model system for microalgal farming and hydroponic crop production.

Reason Maintenance in Product Modelling via Open Source CAD System

The present and future challenges of a new product design, forecasting and risk management launch strategy for a new product modelling decision process. This paper intends to propose and to look towards the development of a low-cost integrated CAD-CAPP-CAD/CAM product modelling system for the design and manufacture of a proposed product. It is a mapping between several design phases like functional design, technical design and physical design. The modelling data generation process begins with the drafting of a product to be maintained using the drafting software package. From the CAD drawing, the data are transferred to be used as the product models and a CAPP software package will then prepare the operational parameters for the manufacturing of the product. These process data are relayed to a CAM software package, which will then generate the automating information-processing functions. The final stage of the function is to support design and manufacturing operations that may have reaped many benefits in terms of its initial equipment and software costs.

A model system for off-season sweet cherry production in northern China

A model system for off-season sweet cherry production in northern China

Investigation of the NADH/NAD+ ratio in Ralstonia eutropha using the fluorescence reporter protein Peredox

Ralstonia eutropha is a hydrogen-oxidizing (“Knallgas”) bacterium that can easily switch between heterotrophic and autotrophic metabolism to thrive in aerobic and anaerobic environments. Its versatile metabolism makes R. eutropha an attractive host for biotechnological applications, including H2-driven production of biodegradable polymers and hydrocarbons. H2 oxidation by R. eutropha takes place in the presence of O2 and is mediated by four hydrogenases, which represent ideal model systems for both biohydrogen production and H2 utilization. The so-called soluble hydrogenase (SH) couples reversibly H2 oxidation with the reduction of NAD+ to NADH and has already been applied successfully in vitro and in vivo for cofactor regeneration. Thus, the interaction of the SH with the cellular NADH/NAD+ pool is of major interest. In this work, we applied the fluorescent biosensor Peredox to measure the [NADH]:[NAD+] ratio in R. eutropha cells under different metabolic conditions. The results suggest that the sensor operates close to saturation level, indicating a rather high [NADH]:[NAD+] ratio in aerobically grown R. eutropha cells. Furthermore, we demonstrate that multicomponent analysis of spectrally-resolved fluorescence lifetime data of the Peredox sensor response to different [NADH]:[NAD+] ratios represents a novel and sensitive tool to determine the redox state of cells.