In this study we tested 39 Lactococcus lactis strains isolated from diverse habitats for their robustness under heat and oxidative stress, demonstrating high diversity in survival (up to 4 log units). Strains with an L. lactis subsp. lactis phenotype generally displayed more-robust phenotypes than strains with an L. lactis subsp. cremoris phenotype, whereas the habitat from which the strains had been isolated did not appear to influence stress survival. Comparison of the stress survival phenotypes with already available comparative genomic data sets revealed that the absence or presence of specific genes, including genes encoding a GntR family transcriptional regulator, a manganese ABC transporter permease, a cellobiose phosphotransferase system (PTS) component, the FtsY protein, and hypothetical proteins, was associated with heat or oxidative stress survival. Finally, 14 selected strains also displayed diversity in survival after spray drying, ranging from 20% survival for the most robust strains, which appears acceptable for industrial application, to 0.1% survival for the least-tolerant strains. The high and low levels of survival upon spray drying correlated clearly with the combined robustness under heat and oxidative stress. These results demonstrate the relevance of screening culture collections for robustness under heat and oxidative stress on top of the typical screening for acidifying and flavor-forming properties. © 2014, American Society for Microbiology.
The present study focuses on the level of stress a teacher perceives when dealing with the most behaviorally challenging student in his or her classroom. To measure stress in Dutch elementary classrooms, a sample was drawn of 582 teachers. Two questions concerning this relation between student and teacher will be addressed. First of all, we focus on background variables of teachers and students as sources of variation in explaining the magnitude of challenging student behavior and the associated level of stress teachers experience. The second topic of this paper is to accommodate the potentially stressful relationship between student and teacher in a wider network of surrounding variables, which are, Self-efficacy, Negative affect, Autonomy in taking decisions, and Support amongst colleagues. To evaluate the presence of challenging behavior, the behavior of the student is related to more general variables like student responsibility, class size and ratio of boys to girls. We close our paper by assessing the validity of the studied relationship between teacher and student with respect to possible burnout.
In de afgelopen jaren groeide het besef dat veel inwoners die een beroep doen op de publieke dienstverlening de nodige stress en zorgen ervaren. Werkloosheid, hoge schulden of problemen in de opvoeding kunnen eraan bijdragen dat het leven van mensen meer vraagt dan zij aankunnen. Het besef dat chronische stress een wissel trekt op het functioneren heeft een groeiende groep publieke dienstverleners geïnspireerd om in de ondersteuning die zij inwoners bieden, (meer) rekening te houden met de doorwerking van de stress op gedrag. Dat een aanhoudend stroom van zorgen verklaart waarom inwoners die hulp nodig hebben te vaak niet in staat blijken om de processtappen te zetten die van hen worden gevraagd: stukken aanleveren, geen afspraken missen, solliciteren, rondkomen van weekgeld, et cetera. Een van de belangrijkste middelen voor professionals om inwoners te motiveren en te ondersteunen de processtappen toch te zetten is het gesprek. Veel professionals (en hun management) hebben de neiging om vooral aandacht te besteden aan de inhoud van die gesprekken. Een verkenning van studies naar de impact van inrichting op ervaren stress leert dat ook de inrichting van een gebouw kan bijdragen aan stress-sensitieve dienstverlening. Op verzoek van de gemeente Utrecht en in nauwe samenwerking met Studio Sociaal Centraal heeft het lectoraat Schulden en Incasso een literatuurverkenning uitgevoerd om de gemeente Utrecht en andere uitvoerders van publieke dienstverlening op weg te helpen bij het inrichten van ontmoetingsruimten voor professionals die uitvoering geven aan onder meer de schuldhulpverlening, re-integratie, Wmo, jeugdhulpverlening en jeugdgezondheidszorg.
Recycling of plastics plays an important role to reach a climate neutral industry. To come to a sustainable circular use of materials, it is important that recycled plastics can be used for comparable (or ugraded) applications as their original use. QuinLyte innovated a material that can reach this goal. SmartAgain® is a material that is obtained by recycling of high-barrier multilayer films and which maintains its properties after mechanical recycling. It opens the door for many applications, of which the production of a scoliosis brace is a typical example from the medical field. Scoliosis is a sideways curvature of the spine and wearing an orthopedic brace is the common non-invasive treatment to reduce the likelihood of spinal fusion surgery later. The traditional way to make such brace is inaccurate, messy, time- and money-consuming. Because of its nearly unlimited design freedom, 3D FDM-printing is regarded as the ultimate sustainable technique for producing such brace. From a materials point of view, SmartAgain® has the good fit with the mechanical property requirements of scoliosis braces. However, its fast crystallization rate often plays against the FDM-printing process, for example can cause poor layer-layer adhesion. Only when this problem is solved, a reliable brace which is strong, tough, and light weight could be printed via FDM-printing. Zuyd University of Applied Science has, in close collaboration with Maastricht University, built thorough knowledge on tuning crystallization kinetics with the temperature development during printing, resulting in printed products with improved layer-layer adhesion. Because of this knowledge and experience on developing materials for 3D printing, QuinLyte contacted Zuyd to develop a strategy for printing a wearable scoliosis brace of SmartAgain®. In the future a range of other tailor-made products can be envisioned. Thus, the project is in line with the GoChem-themes: raw materials from recycling, 3D printing and upcycling.
Our unilateral diet has resulted in a deficiency of specific elements/components needed for well-functioning of the human body. Especially the element magnesium is low in our processed food and results in neuronal and muscular malfunctioning, problems in bone heath/strength, and increased chances of diabetes, depression and cardiovascular diseases. Furthermore, it has also been recognized that magnesium plays an important role in cognitive functioning (impairment and enhancement), especially for people suffering from neurodegenerative diseases (Parkinson disease, Alzheimer, etc). Recently, it has been reported that magnesium addition positively effects sleep and calmness (anti-stress). In order to increase the bioavailability of magnesium cations, organic acids such as citrate, glycerophosphate and glycinate are often used as counterions. However, the magnesium supplements that are currently on the market still suffer from low bio-availability and often do not enter the brain significantly.The preparation of dual/multiple ligands of magnesium in which the organic acid not only functions as a carrier but also has synergistically/complementary biological effects is widely unexplored and needs further development. As a result, there is a strong need for dual/multiple magnesium supplements that are non-toxic, stable, prepared via an economically and ecologically attractive route, resulting in high bioavailability of magnesium in vivo, preferably positively influencing cognition/concentration
Currently, many novel innovative materials and manufacturing methods are developed in order to help businesses for improving their performance, developing new products, and also implement more sustainability into their current processes. For this purpose, additive manufacturing (AM) technology has been very successful in the fabrication of complex shape products, that cannot be manufactured by conventional approaches, and also using novel high-performance materials with more sustainable aspects. The application of bioplastics and biopolymers is growing fast in the 3D printing industry. Since they are good alternatives to petrochemical products that have negative impacts on environments, therefore, many research studies have been exploring and developing new biopolymers and 3D printing techniques for the fabrication of fully biobased products. In particular, 3D printing of smart biopolymers has attracted much attention due to the specific functionalities of the fabricated products. They have a unique ability to recover their original shape from a significant plastic deformation when a particular stimulus, like temperature, is applied. Therefore, the application of smart biopolymers in the 3D printing process gives an additional dimension (time) to this technology, called four-dimensional (4D) printing, and it highlights the promise for further development of 4D printing in the design and fabrication of smart structures and products. This performance in combination with specific complex designs, such as sandwich structures, allows the production of for example impact-resistant, stress-absorber panels, lightweight products for sporting goods, automotive, or many other applications. In this study, an experimental approach will be applied to fabricate a suitable biopolymer with a shape memory behavior and also investigate the impact of design and operational parameters on the functionality of 4D printed sandwich structures, especially, stress absorption rate and shape recovery behavior.