Biotechnological uses of Azotobacter vinelandii: Current state, limits and prospects

Azotobacter vinelandii is a bacterium obligate aerobe able to fix nitrogen and grow under microaerophilic conditions. This microorganism has remarkable cellular machinery with the ability to biosynthesize three molecules of important biotechnological and biomedical applications: the extracellular polysaccharide alginate, the intracellular polyester poly-β-hydroxybutyrate (PHB) and siderophores compounds. Alginate and PHB have been produced in shake flasks and bioreactors (at laboratory scale) under different environmental and nutritional conditions. This mini-review gives a current overview on the application of wild-type and mutant’s strains of A. vinelandii in bioprocesses to produce alginate or PHB. Scales of production implemented and fermentation strategies used as well as the potential limitations of the use of A. vinelandii cells are analyzed. Based on an approach that integrates molecular and bioengineering techniques, new experimental strategies to enhance the productivity of alginate and PHB from A. vinelandii are proposed.Keywords: Azotobacter vinelandii, alginate, poly-β-hydroxybutyrate, siderophores, bioprocess, scales of productionAfrican Journal of Biotechnology Vol. 9(33), pp. 5240-5250, 16 August, 201

DESIGN AND INTEGRATION OF A HUMAN-ROBOT PHYSICAL INTERACTION PLATFORM WITH PURPOSES OF MEDICAL DIAGNOSIS AND REHABILITATION OF UPPER LIMB

In this paper a human-robot physical interaction system with purposes of diagnosis and rehabilitation of upper limb is proposed.Anunderactuatedhaptic device with six degrees of freedom is used, with low inertia and low joint friction.Adaptive control technique is used for passive haptic guidance and active exploration, in order to compensate the dynamic uncertainty of the human operator in the loop.To validate the experimental platform, a procedure is established with three steps: i) knowledge of the haptic interface (interaction with the kinematic virtual environment), ii) navigation in a virtual pipe with changes in the geometric characteristics (verification of position, velocity, collisions and runtime), and iii) haptic guidance in a structured path based on a clinical protocol (study of convergence and energy).Environmental conditions such as temperature, humidity, lighting and noise are characterizedwith purposes to define experimental conditions.In this work, we assess based on the NASA-TLX protocol,the workload perception of simple temporal-spatial tasks

DESIGN AND INTEGRATION OF A HUMAN-ROBOT PHYSICAL INTERACTION PLATFORM WITH PURPOSES OF MEDICAL DIAGNOSIS AND REHABILITATION OF UPPER LIMB

In this paper a human-robot physical interaction system with purposes of diagnosis and rehabilitation of upper limb is proposed.Anunderactuatedhaptic device with six degrees of freedom is used, with low inertia and low joint friction.Adaptive control technique is used for passive haptic guidance and active exploration, in order to compensate the dynamic uncertainty of the human operator in the loop.To validate the experimental platform, a procedure is established with three steps: i) knowledge of the haptic interface (interaction with the kinematic virtual environment), ii) navigation in a virtual pipe with changes in the geometric characteristics (verification of position, velocity, collisions and runtime), and iii) haptic guidance in a structured path based on a clinical protocol (study of convergence and energy).Environmental conditions such as temperature, humidity, lighting and noise are characterizedwith purposes to define experimental conditions.In this work, we assess based on the NASA-TLX protocol,the workload perception of simple temporal-spatial tasks

Gestão de processos de negócios em serviços de tecnologia e informação

En este trabajo definimos y simulamos procesos en una compañía que presta servicios de tecnología de la información con el propósito de mejorar la atención y las funciones definidas en cada proceso. Analizamos diversos trabajos con respecto a la gestión de procesos de negocios y simulación. Para nuestro modelo de desarrollo, diseñamos una metodología basada en la gestión de procesos de negocios. Los procesos y las actividades fueron modelados y simulados con la ayuda de una herramienta de software para estables los tiempos y el número deposibles estancias ejecutadas. Dichos tiempos y procesos pueden ser adaptados al nivel de rendimiento deseado. El resultado de dichos procesos contribuyó a la realización de actividades de negocio de tal manera que las mismas sean más eficientes con respecto al uso del tiempo y por lo tanto otorguen un servicio de alta calidad.In this work, we defined and simulated processes in a company which provides Information Technology services with the purpose of enhancing attention and functions defined for each process. We analyzed several works related to business management process and simulation. For model development, we designed a methodology based on Business Process Management. Processes and activities were modelled and simulated using a software tool establishing times and number of possible instances to be performed. These times and processes may be adapted to a desired level of performance. Resulting processes contribute to perform business activities in a more adequate way and be more time efficient in order to provide a higher quality service

Fog interception by Ball moss (<i>Tillandsia recurvata</i>)

Interception losses are a major influence in the water yield of vegetated areas. For most storms, rain interception results in less water reaching the ground. However, fog interception can increase the overall water storage capacity of the vegetation and once the storage is exceeded, fog drip is a common hydrological input. Fog interception is disregarded in water budgets of semiarid regions, but for some plant communities, it could be a mechanism offsetting evaporation losses. <i>Tillandsia recurvata</i> is a cosmopolitan epiphyte adapted to arid habitats where fog may be an important water source. Therefore, the interception storage capacity by <i>T. recurvata</i> was measured in controlled conditions and applying simulated rain or fog. Juvenile, vegetative specimens were used to determine the potential upperbound storage capacities. The storage capacity was proportional to dry weight mass. Interception storage capacity (<i>C</i>_min) was 0.19 and 0.56 mm for rainfall and fog respectively. The coefficients obtained in the laboratory were used together with biomass measurements for <i>T. recurvata</i> in a xeric scrub to calculate the depth of water intercepted by rain. <i>T. recurvata</i> contributed 20 % to the rain interception capacity of their shrub hosts: <i>Acacia farnesiana</i> and <i>Prosopis laevigata</i> and; also potentially intercepted 4.8 % of the annual rainfall. Nocturnal stomatic opening in <i>T. recurvata</i> is not only relevant for CO₂ but for water vapor, as suggested by the higher weight change of specimens wetted with fog for 1 h at dark in comparison to those wetted during daylight (543 ± 77 vs. 325 ± 56 mg, <i>p</i> = 0.048). The storage capacity of <i>T. recurvata</i> leaf surfaces could increase the amount of water available for evaporation, but as this species colonise montane forests, the effect could be negative on water recharge, because potential storage capacity is very high, in the laboratory experiments it took up to 12 h at a rate of 0.26 l h⁻¹ to reach saturation conditions when fog was applied

SDSS-IV MANGA: Spatially Resolved Star Formation Main Sequence and LI(N)ER Sequence

We present our study on the spatially resolved H_alpha and M_star relation for 536 star-forming and 424 quiescent galaxies taken from the MaNGA survey. We show that the star formation rate surface density (Sigma_SFR), derived based on the H_alpha emissions, is strongly correlated with the M_star surface density (Sigma_star) on kpc scales for star- forming galaxies and can be directly connected to the global star-forming sequence. This suggests that the global main sequence may be a consequence of a more fundamental relation on small scales. On the other hand, our result suggests that about 20% of quiescent galaxies in our sample still have star formation activities in the outer region with lower SSFR than typical star-forming galaxies. Meanwhile, we also find a tight correlation between Sigma_H_alpha and Sigma_star for LI(N)ER regions, named the resolved "LI(N)ER" sequence, in quiescent galaxies, which is consistent with the scenario that LI(N)ER emissions are primarily powered by the hot, evolved stars as suggested in the literature.Comment: 6 pages, 4 figures. ApJ Letter accepte

Effect of the Fe Nanoparticles Generated by Pulsed Plasma in Liquid in the Catalyzed Ozone Removal of Phenolphthalein

We have synthesized, in this work, zero valent iron (ZVI) nanoparticles to improve the efficiency of degradation of phenolphthalein catalyzed by ozone in aqueous solution. The Fe nanoparticles were obtained using the pulsed plasma in liquid (PPL) method with water as the liquid medium. Such nanoparticles have a mean size of 12 nm and are composed of ~80% Fe0, while the rest are a mixture of Fe+2 and Fe+3 oxides. The degradation of phenolphthalein was carried on a glass reactor injecting a constant amount of ozone and introducing different concentrations of Fe nanoparticles to the system. When using pure ozone, the percentage of degradation of phenolphthalein measured by colorimetry after one hour of reaction was 84%. However, when Fe nanoparticles are used, such percentage can be as high as 98% in 50 minutes of reaction. Furthermore, the degradation rate constant was 0.0334 min−1 with only ozone and it can be as high as 0.0733 min−1 with Fe nanoparticles. Finally, the total mineralization of phenolphthalein was obtained by total organic carbon (TOC) determinations. It is shown that when using only ozone, we obtained a percentage of mineralization of 49% and 96% when using the highest concentration of Fe nanoparticles