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Increasing the use of bioethanol fuel is an option for reducing greenhouse gas emissions, although there is still room for improvement in the industrial production processes. Simulation tools can assist in improving industrial operations, but the models presented so far in the literature to describe bioethanol production from sugar cane were developed under conditions far from industrial reality, at the bench scale and with highly controlled fermentation variables. This hampers the use of these models to find optimized input conditions to increase industrial bioethanol production. In the present work, a framework based on artificial intelligence techniques combining the Artificial Neural Network (ANN) model and Particle Swarm Optimization (PSO) algorithm was developed to optimize industrial bioethanol production. Industrial data from a mill in the state of São Paulo (Brazil) were used to train the ANN. The databank comprised 3400 experimental values (200 operation days) of the whole fermentation unit. The trained ANN model was able to predict the bioethanol concentration at the end of the process with high accuracy and enabled the optimization of the input variables to maximize bioethanol production of the mill using the PSO algorithm. The results showed an increase of about 10% in bioethanol concentration and production at the end of fermentation per harvest for the industrial unit taken as a case study. This new approach enhances the knowledge about the industrial ethanol fermentation process and can become a tool to guide new studies regarding the increase of biofuels production, mainly the ones which present behavior with high nonlinearity.

The hydrodynamic environment in bioreactors is an important parameter because cultivation conditions that provide satisfactory oxygen transfer rates tend to be harmful to microorganisms, due to the effect of shear on the cellular structure. Consequently, it is a challenge to find the ideal set of bioreactor operating conditions that favor production of the metabolites of interest. The present work evaluated the fragmentation of Aspergillus nigerpellets in two different types of bioreactor: a conventional stirred tank bioreactor (STB) and a concentric-duct airlift (CDA) bioreactor. Both were operated under similar oxygen transfer or shear conditions. Oxygen transfer was quantified by means of the volumetric oxygen transfer coefficient (kLa). The shear condition was determined using the average shear rate (γ̇av), obtained using computational fluid dynamics (CFD), together with pellet fragmentation. The findings showed that the CDA bioreactor caused less fragmentation of the pellets, compared to the STB, when both systems were operated with the same kLa values. For similar fragmentation levels, the kLa value for the CDA bioreactor was 38% higher than observed for the STB. Considering the results for both bioreactor models, the fragmentation of A. nigerpellets, represented by the variation of the average normalized A. nigerpellet equivalent diameter (Deq/Deq,0) after fragmentation assays of 4 h duration (Δfrag), exhibited a linear relation with γav(R2= 0.97). The CDA bioreactor also presented advantages in terms of specific power consumption and mass transfer efficiency. These results should assist in the selection of suitable bioreactor models and operating conditions, in order to improve the efficiency of industrial production of bio-based products.

The hydrodynamics and mass transfer characteristics of ethanol stripping with CO2were evaluated for a 2.0-L pneumatic bioreactor operated in bubble column (BC), concentric-tube airlift (CTA), and split-cylinder airlift (SCA) configurations, as well as for bubble columns with three different working volumes (2.0, 5.0, and 10.0 L). The results showed that an increase of the global gas hold-up (ɛG) did not enhance ethanol removal in any of these prototypes. The volumetric ethanol removal coefficient (kLEa) values were very similar for the three models, despite the higher ɛGobtained for the CTA configuration. The same behavior was observed for the three scales of BC prototypes, except for distinct behavior observed at the 10.0-L scale operated above 2.5 vvm. In order to predict kLEa for different scales and operational conditions, a dimensionless correlation was proposed for the Sherwood number, which provided an excellent fit to the experimental data, with few points exceeding ±10% deviation. The ethanol concentration factor (FC) values increased with decrease of the specific gas flow rates, with the highest FCvalue of around 6.0 (6 times the original solution concentration) obtained for the 10.0-L scale of BC. Therefore, increasing the prototype size led to an increase of Fc, resulting in greater ethanol enrichment of the gas stream leaving the equipment.

Clinical practice guidelines for dietary intake in hemodialysis focus on individual nutrients. Little is known about associations of dietary patterns with survival. We evaluated the associations of dietary patterns with cardiovascular and all-cause mortality among adults treated by hemodialysis.

One way of overcoming the substrate and ethanol inhibition effects in the industrial ethanol production process is to use fed-batch fermentation coupled with an ethanol removal technique. This work describes the optimization and experimental validation of sugar cane ethanol production by fed-batch fermentation with in situ ethanol removal by CO2stripping. The optimization employing a genetic algorithm (GA) was used to find the optimum feed flow rate (F) and the ethanol concentration (CE0) in the medium at which to initiate stripping, in order to obtain maximum ethanol productivity. Conventional ethanol fermentation employing the optimum feed flow rate was performed with must containing 257.1 g L–1of sucrose (180 g L–1of total sucrose concentration), resulting in achievement of an ethanol concentration of 82.2 g L–1. The stripping fed-batch fermentation with high total sucrose concentration (260–300 g L–1) or 371.4–428.6 g L–1in the must feeding was performed with optimal values of the feed flow rate and the ethanol concentration (CE0) in the medium at which to initiate stripping. At the highest sucrose feed (total concentration of 300 g L–1), the total ethanol concentration reached 136.9 g L–1(17.2 °GL), which was about 65% higher than the value obtained in fed-batch fermentation without ethanol removal by CO2stripping. This strategy proved to be a promising way to minimize inhibition by both the substrate and ethanol, leading to increased sugar cane ethanol production, reduced vinasse generation, and lower process costs.

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To study the practice patterns for the management of acute postoperative and postinjection endophthalmitis.

Ethanol removal by CO2stripping during alcoholic fermentation is one way of overcoming the problem of inhibition by the product. However, the lack of efficient methods to recover ethanol from the gas phase still makes the use of stripping unviable. In this work, gas absorption was evaluated as a method for the recovery of ethanol from the gas mixture generated by CO2stripping. First, the solvents water, monoethylene glycol (MEG), and diethylene glycol were evaluated in terms of their performance in ethanol absorption. MEG was selected as the most appropriate absorbent because it provided a satisfactory ethanol recovery percentage, in addition to the fact that it is already used in distilleries to obtain anhydrous ethanol. Subsequent assays using MEG were conducted to investigate the influence of the initial MEG volume in the absorber, the recirculation volumetric flow rate of solvent, and the use of two absorbers connected in series. A modeling procedure was developed based on mass balance equations for the species involved (ethanol, water, CO2, and MEG), stripping and absorption kinetics, and vapor–liquid equilibrium concepts and was able to accurately describe the process behavior. The use of two absorbers, each with 0.80 L of MEG, enabled recovery of up to 93.1% of the ethanol from the stripping gas mixture. The results showed that gas absorption with MEG is a highly promising strategy for ethanol recovery, with potential for applications in industrial ethanol fermentation processes.

Visually impaired children and adults have difficulties in engaging in positive social interactions. This paper assesses social competence in sighted and visually impaired people and to propose a novel interventional strategy in visually impaired children. We designed a task that assesses the ability to initiate and sustain an interaction with the experimenter while performing free hand movements using a sonorous feedback on the experimenter's wrist. Both participant and experimenter kinematic data were recorded with a motion capture system. The level of social interaction between participant and experimenter has been computed through objective measurements based on Granger causality analysis applied to the participant arm kinematics. The interventional program followed by the visually impaired children lasted 12 weeks and consisted in a series of spatial and social games performed with the use of a sonorous bracelet which provides an auditory feedback of body actions in space. Visually impaired individuals present a poorer communication flow with the experimenter than sighted people, which indicates a less efficient social interaction. The amount of communication between the two agents resulted in a significant improvement after the interventional program. Thus, a specific intervention, based on the substitution of visual with auditory feedback of body actions, can enhance social inclusion for the blind population.

The Puerto Princesa Underground River, amongst the largest caves of the Philippine Islands, is the most visited show cave in the country, even though it has undergone no tourism adaptation at all. Its scientific importance primarily relies on the fact that it is one of the largest known underground estuaries in the world, and the effect of tides is visible along more than 7 km of the cave length. The complex relationships between sea and freshwater influence not only the hydrodynamics of the system and the speleogenetic processes presently active, but also its climate and its ecosystem. The systematic exploration and research of this coastal karst system started some 40 years ago and have shown that the Puerto Princesa Underground River is one of the most important caves in the world with regard to many different scientific fields. Speleogenesis concerns the initial phreatic solution followed by vadose erosion with periodical marine invasion, and subsequent saline/freshwater-mixing processes during sea-level highstands. The hydrodynamic behaviour of the water flowing inside the cave is rather complex, being simultaneously controlled by allogenic recharge and tides. Speleothems abundantly occur with several forms, some of which have never been described before. Several minerals, some of which are very rare, are present, together with palaeontological remains exposed by differential corrosion on rock walls. Last but not least, two large populations of bats and swiftlets sustain a complex subterranean ecosystem.

Three major problems in cave micrometeorology are analysed: the concept of the temperature of a cave and its phenomenology; the internal energy flows and consequent local entropy production; and a non-hydrostatic physical model of the underground convective air circulation. A cave's temperature is rich in information, but it is often difficult to obtain because it requires experimental accuracies to be pushed beyond the reach of common external meteorological instruments to detect a variety of factors, such as thermal sedimentation, seasonal variations and the effects of external morphology. Energy flow has an essential role in estimating the sensitivity of a cave to external inputs. A model for evaluating the local entropy production is developed. Entropy seems to be the most basic parameter, explaining both the sensitivity of the environment and its tendency to form complex structures. Analysis of the second-order terms of convective air circulation is more complex than expected; nevertheless, only such an analysis is able to explain the behaviours (e.g. continuity in the airflow) that cannot be predicted by the first-order models.

Human to human sensorimotor interaction can only be fully understood by modeling the patterns of bodily synchronization and reconstructing the underlying mechanisms of optimal cooperation. We designed a tower-building task to address such a goal. We recorded upper body kinematics of dyads and focused on the velocity profiles of the head and wrist. We applied recurrence quantification analysis to examine the dynamics of synchronization within, and across the experimental trials, to compare the roles of leader and follower. Our results show that the leader was more auto-recurrent than the follower to make his/her behavior more predictable. When looking at the cross-recurrence of the dyad, we find different patterns of synchronization for head and wrist motion. On the wrist, dyads synchronized at short lags, and such a pattern was weakly modulated within trials, and invariant across them. Head motion, instead, synchronized at longer lags and increased both within and between trials: a phenomenon mostly driven by the leader. Our findings point at a multilevel nature of human to human sensorimotor synchronization, and may provide an experimentally solid benchmark to identify the basic primitives of motion, which maximize behavioral coupling between humans and artificial agents.

AbstractA mycological investigation carried out in the hydrothermal caves of Monte Kronio, located in Sicily (southern Italy), is reported. This particular hydrothermal cave system is characterized by temperatures up to 37 °C and relative humidity close to 100%. In spite of the harsh conditions, which are prohibitive for most organisms, we counted 160 vital Morphological Taxonomic Units and identified 14 taxa during a survey of the system. The most prevalent genera were Penicillium, Cladosporiumand Trametes. Furthermore, we report the first recorded occurrence of Metarhizium flavoviridevar. flavoviridein a hypogean environment.