Systematic optimization of human pluripotent stem cells media using Design of Experiments.

Human pluripotent stem cells (hPSC) are used to study the early stages of human development in vitro and, increasingly due to somatic cell reprogramming, cellular and molecular mechanisms of disease. Cell culture medium is a critical factor for hPSC to maintain pluripotency and self-renewal. Numerous defined culture media have been empirically developed but never systematically optimized for culturing hPSC. We applied design of experiments (DOE), a powerful statistical tool, to improve the medium formulation for hPSC. Using pluripotency and cell growth as read-outs, we determined the optimal concentration of both basic fibroblast growth factor (bFGF) and neuregulin-1 beta 1 (NRG1β1). The resulting formulation, named iDEAL, improved the maintenance and passage of hPSC in both normal and stressful conditions, and affected trimethylated histone 3 lysine 27 (H3K27me3) epigenetic status after genetic reprogramming. It also enhances efficient hPSC plating as single cells. Altogether, iDEAL potentially allows scalable and controllable hPSC culture routine in translational research. Our DOE strategy could also be applied to hPSC differentiation protocols, which often require numerous and complex cell culture media

Portuguese Students’ Perceptions About the Motivational Climate in Physical Education

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Examining Portuguese High School Students’ Attitudes Toward Physical Education

Portugal ranks fourth among countries with the highest rate of overweight population, considering that 67.6% of the Portuguese population over the age of 15 is overweight or obese. To our knowledge, limited studies have investigated students' attitudes toward physical education in Portugal. Such research is necessary because it can provide valuable insights for policy and application in the curriculum development for physical education, which may eventually increase participation in physical and sports activities. This study analyzed students' attitudes toward physical education (PE) according to sociodemographic variables, including grade level, socioeconomic status, and gender, and their participation in extracurricular sports activities and respective PE grades. The sample comprised 476 high school students (from the 7th, 8th, and 9th-grade levels) from five public schools located in Portugal. The Students' Attitudes toward Physical Education Questionnaire was adapted and validated for use with Portuguese students as a two-factor model. Findings show that students generally have a moderately positive attitude toward PE. However, students' positive attitudes tend to decrease throughout high school, which is particularly significant in the 9th grade. Furthermore, students' attitudes are influenced by gender, extracurricular sports practice, and grades. These findings may help stakeholders reflect on how to frame PE in a more meaningful way to create a solid foundation for maintaining an active lifestyle throughout life. Implications for further research and practice are discussed.info:eu-repo/semantics/publishedVersio

Interfacial stabilization of enzymes in microemulsions

One of the major constrains to the use of enzymes in industrial processes is their insufficient stability under processing conditions, namely high temperatures, presence of ultrasounds, among others. Herein, we investigated the use of oil-in-water proteinaceous (BSA) microemulsions as a novel methodology for the stabilization of laccase from ascomycete Micelliophthora thermophila. The immobilization of laccase onto the produced microemulsions benefitiated its stability under ultrasonic conditions. The half life time of immobilized laccase was 2.4-fold higher (from 23 to 56 minutes) than laccase in the free form. This technique show promising potentialities for the stabilization of enzymes used onto a variety of processes, namely textile bleaching, surface hydrolysis, among others

13th FINA World Championships: analysis of swimsuits used by elite male swimmers

The purpose of this study was to describe the distribution of different swimsuits models used by male swimmers during all the finals at the 13th FINA World Championships, being held at Rome in 2009. Simultaneously, it was intended to verify the distribution of the different swimsuits used along the distances of the freestyle finals, and thus to understand the preferences of the top-level swimmers. It were used the results databases from the 13th FINA World Championships, in Rome 2009. Only the male swimmers participating at the finals were analyzed, for a total number of 17 individual swimming events. The wear swimsuit by each swimmer in a given event was observed from video recorded of the television broadcast. Male swimmers participating in the finals limited their choice to seven types of commercial swimsuits, of four different sports brands. Jaked01 Full® was the most used (47.07%), followed by the Powerskin X-Glide Full® (34.56%), the Powerskin X-Glide Pants® (7.35%) and the LZR Racer Full® (5.15%). In freestyle swimming events most of the male swimmers choose to wear full body swimsuits. Jaked01 Full® was predominant in the 50 m event, with 62.50% of swimmers choices. This value decreases to 25.00% when analyzing 100 m event, and remained similar over the longer distances swum. The Powerskin X-Glide Full® was used for 37.50% of the swimmers in 50 m swimming event, and it increases to 62.50% for the 100 m freestyle. These results seem to demonstrate that swimmers have preferences for full swimsuits, and for these two swimsuits, the Powerskin X-Glide Full® and the Jaked01 Full®

THE EFFECT OF DEPTH ON THE DRAG FORCE DURING UNDERWATER GLIDING: A CFD APPROACH

Swimming events are the sum of a gliding part and a swimming part. The gliding is used after the start and turns, and this phase typically corresponds to 10-25% of the total event time (Chatard et al., 1990). Taking this into account, one can notice that gliding is very important in swimming events and, therefore, its biomechanical study in order to make it more efficient is also very relevant. The gliding can be studied experimentally, by using voluntary subjects gliding in a controlled manner in a swimming pool (using video or velocimetry, for instance), or by using Computational Fluid Dynamics (CFD). Although the experimental method gives “real” values it also presents some drawbacks, like usually imposing a heavy setup and also the fact that it is difficult to control all variables, like depth, attitude or intersegment positions of the swimmer. The CFD method does not have these limitations and its results are comparable to those obtained by the experimental method (Bixler & Riewald, 2002; Silva et al., 2005; Bixler et al., 2007; Vilas Boas et al., 2010). This work aims to study the effects of the depth and velocity on the drag force experienced by a swimmer during gliding using the CFD method

Sonochemical and hydrodynamic cavitation reactors for laccase/hydrogen peroxide cotton bleaching

Article in pressThe main goal of this work is to develop a novel and environmental-friendly technology for cotton bleaching with reduced processing costs. This work exploits a combined laccase–hydrogen peroxide process assisted by ultrasound. For this purpose, specific reactors were studied, namely ultrasonic power generator type K8 (850 kHz) and ultrasonic bath equipment Ultrasonic cleaner USC600TH (45 kHz). The optimal operating conditions for bleaching were chosen considering the highest levels of hydroxyl radical production and the lowest energy input. The capacity to produce hydroxyl radicals by hydrodynamic cavitation was also assessed in two homogenizers, EmulsiFlex®-C3 and APV-2000. Laccase nanoemulsions were produced by high pressure homogenization using BSA (bovine serum albumin) as emulsifier. The bleaching efficiency of these formulations was tested and the results showed higher whiteness values when compared to free laccase. The combination of laccase–hydrogen peroxide process with ultrasound energy produced higher whiteness levels than those obtained by conventional methods. The amount of hydrogen peroxide was reduced 50% as well as the energy consumption in terms of temperature (reduction of 40 °C) and operating time (reduction of 90 min).The author Idalina Goncalves would like to acknowledge the Cottonbleach project (FP7-SME-2008-2; 243529-2-cottonbleach) for the funding. The author Carla Silva would like to acknowledge FCT - Fundacao para a Ciencia e a Tecnologia for the grant SFRH/BPD/46515/2008

Maize plants produce direct resistance elicited by Tetranychus urticae Koch (Acari: Tetranychidae).

Plants can be attacked by a wide variety of herbivores. Thus, developing protective mechanisms for resistance against these agents is an advantage for survival and reproduction. Over the course of evolution, many resistance mechanisms against herbivory have been developed by the plants. Induced direct and indirect resistance mechanisms can manifest in plants after herbivore attack. The two-spotted spider mite Tetranychus urticae is not a pest of maize crops (Zea mays), despite being reported infesting plants that may have resistances against this herbivore. We tested the hypothesis that maize plants would be able to induce direct resistance against T. urticae after, evaluating the effect of T. urticae infestation in maize plants on the development and reproduction of conspecifics. We tested induced direct resistance performing infestation and measuring biological parameters upon a second infestation. Maize plants, 40 days after sowing, were divided into two groups: 30 not infested by T. urticae (clean plants clean) and, 30 infested by the spider mite. Infestation of maize plants by T. urticae reduced the conspecific female adult survival. However, no change in the survival of immature or reproduction was observed. These results suggest the induction of induced direct resistances in maize by T. urticae. This is first report of direct resistance induction in Z. mays by the two-spotted spider mite T. urticae

Polyoxometalate/laccase-mediated oxidative polymerization of catechol for textile dyeing

The synergistic effect between polyoxometalates (POMs), namely K5[SiW11VVO40]·11H2O and H5[PMo10 VV2O40]·13H2O and laccase from ascomycete Myceliophthora thermophila has been employed for the first time in oxidative polymerization of catechol. Such a laccase-mediator system allowed the formation of a relatively high molecular weight polycatechol as confirmed by size exclusion chromatography and electrospray ionization mass spectrometry (ESI-MS) (3990 Da when using K5[SiW11VVO40]·11H2O and 3600 Da with H5[PMo10VV 2O40]·13H2O). The synthesized polymers were applied as dyes for the dyeing of flax fabrics. The color intensity of flax fabrics colored with polymer solutions was evaluated by diffuse reflectance spectrophotometry via k/s measurements (+10% of fixation ratio). A new synthetic process allowed a dyeing polymer, provided upon flax coloration, better color fixation and color resistance when compared to that obtained by conventional synthesis with laccase solely or with addition of organic mediator (1-hydroxybenzotriazole)

Functionalization of gauzes with liposomes entrapping an anti-inflammatory drug: a strategy to improve wound healing

From ancientness, suitable materials have been developed to cover the wounds in order to prevent infections and promote proper wound healing. In this study, the successful development of functionalized nonwoven gauzes with liposomes entrapping anti-inflammatory piroxicam is reported. Piroxicam is a non-steroidal anti-inflammatory drug (NSAID) that can suppress a persistent inflammatory response, leading to improved wound healing. The results demonstrated that the highest NSAID concentration released is achieved when gauzes were previously cationized with poly(diallyldimethylammonium chloride) (PDDA) and high concentration of phospholipid (≈3000 μM) and multilamellar liposomes (MLVs) were used. MLVs were also the best vehicle considering their biocompatibility with skin human fibroblasts, where no toxicity was observed for neither of the tested conditions. The developed functionalized gauzes can be, therefore, a good strategy to treat chronic wounds.Helena Ferreira, Teresa Matama and Carla Silva thank POPH/FSE for co-financing and FCT for fellowships SFRH/BPD/38939/2007, SFRH/BPD/47555/2008, SFRH/BPD/46515/2008, respectively. This work was supported by FEDER through POFC - COMPETE and by national funds from FCT through the project PEst-C/BIA/UI4050/2011