轮胎在道路上产生的外部噪声

与日俱增的公众压力和不断变化的车辆测试程序要求轮胎制造商必须设计出静音效果更好的轮胎。在此发表URGENT(认识轮胎在道路上的外部噪声)项目的一些初步研究结果。该项目的一个特点是加强了行业和院校活动的相互配合。该项目涉及一家轮胎制造商(登录普)、一家     

A Magneto-Responsive Hydrogel System for the Dynamic Mechano-Modulation of Stem Cell Niche

The biophysical microenvironment of cells dynamically evolves during embryonic development, leading to defined tissue specification. A versatile and highly adaptive magneto-responsive hydrogel system composed of magnetic nanorods (MNRs) and a stress-responsive polymeric matrix is developed to dynamically regulate the physical stem cell niche. The anisotropic magnetic/shape factor of nanorods is utilized to maximize the strains on the polymeric network, thus regulating the hydrogel modulus in a physiologically relevant range under a minimal magnitude of the applied magnetic fields below 4.5 mT. More significantly, the pre-alignment of MNRs induces greater collective strains on the polymeric network, resulting in a superior stiffening range, over a 500% increase as compared to that with randomly oriented nanorods. The pre-alignment of nanorods also enables a fast and reversible response under a magnetic field of the opposite polarity as well as spatially controlled heterogeneity of modulus within the hydrogel by applying anisotropic magnetic fields. The mechano-modulative capability of this system is validated by a mechanotransduction model with human-induced pluripotent stem cells where the locally controlled hydrogel modulus regulates the activation of mechano-sensitive signaling mediators and subsequent stem cell differentiation. Therefore, this magneto-responsive hydrogel system provides a platform to investigate various cellular behaviors under dynamic mechanical microenvironments.     

Two-Photon Polymerization of Sugar Responsive 4D Microstructures

Stimuli-responsive hydrogels have attracted much attention owing to the versatility of their programmed response in offering intelligent solutions for biomimicry applications, such as soft robotics, tissue engineering, and drug delivery. To achieve the complexity of biomimetic structures, two photon polymerization (2PP) has provided a means of fabricating intricate 3D structures from stimuli-responsive hydrogels. Rapid swelling hydrogel microstructures are advantageous for osmotically driven stimuli-response, where actuation speed, that is reliant on the diffusion of analytes or bioanalytes, can be optimized. Herein, the flexibility of 2PP is exploited to showcase a novel sugar-responsive, phenylboronic acid-based photoresist. This offers a remarkable solution for achieving fast response hydrogel systems that have been often hindered by the volume-dependent diffusion times of analytes to receptor sites. A phenylboronic acid-based photoresist compatible with 2PP is presented to fabricate stimuli-responsive microstructures with accelerated response times. Moreover, microstructures with programmable actuation (i.e., bending and opening) are fabricated using the same photoresist within a one-step fabrication process. By combining the flexibility of 2PP with an easily adaptable photoresist, an accessible fabrication method is showcased for sophisticated and chemo-responsive 3D hydrogel actuators.     

Application of cellulose- and chitosan-based edible coatings for quality and safety of deep-fried foods

Excessive oil uptake and formation of carcinogens, such as acrylamide (AA), heterocyclic amines (HCAs), and polycyclic aromatic hydrocarbons (PAHs), during deep-frying are a potential threat for food quality and safety. Cellulose- and chitosan-based edible coatings have been widely applied to deep-fried foods for reduction of oil uptake because of their barrier property to limit oil ingress, and their apparent inhibition of AA formation. Cellulose- and chitosan-based edible coatings have low negative impacts on sensory attributes of fried foods and are low cost, nontoxic, and nonallergenic. They also show great potential for reducing HCAs and PAHs in fried foods. The incorporation of nanoparticles improves mechanical and barrier properties of cellulose and chitosan coatings, which may also contribute to reducing carcinogens derived from deep-frying. Considering the potential for positive health outcomes, cellulose- and chitosan-based edible coatings could be a valuable method for the food industry to improve the quality and safety of deep-fried foods.