Biodegradable Frequency‐Selective Magnesium Radio‐Frequency Microresonators for Transient Biomedical Implants

Bioresorbable implantable medical devices show a great potential for applications requiring medical care over well‐defined periods of time. Once their function is fulfilled, such implants naturally degrade and resorb in the body, which eliminates adverse long‐term effects or the need for a secondary surgery to extract the implanted device. Since biodegradable materials are water‐soluble, the fabrication of such transient electronic circuits and devices requires special care and needs to rely solely on dry processing steps without exposure to aqueous solutions. A further challenge is the in vivo powering of medical implants that are only constituted of biodegradable materials. This paper describes the design, fabrication, and testing of radio‐frequency biodegradable magnesium microresonators. To this end, an innovative microfabrication process with minimal exposure to aqueous media is developed to fabricate magnesium‐based, water‐soluble electronic components. It consists of a novel sequence of only three steps: one physical vapor deposition, one photolithography, and one ion beam etching step. The frequency‐selective wireless heating of different resonators is demonstrated. This represents a significant step toward their use as power receivers and microheaters in biodegradable implantable medical devices, for applications such as triggered drug release.     

Development of Endothelial Cell Networks in 3D Tissues by Combination of Melt Electrospinning Writing with Cell‐Accumulation Technology

A remaining challenge in tissue engineering approaches is the in vitro vascularization of engineered constructs or tissues. Current approaches in engineered vascularized constructs are often limited in the control of initial vascular network geometry, which is crucial to ensure full functionality of these constructs with regard to cell survival, metabolic activity, and potential differentiation ability. Herein, the combination of 3D‐printed poly‐ε‐caprolactone scaffolds via melt electrospinning writing with the cell‐accumulation technique to enable the formation and control of capillary‐like network structures is reported. The cell‐accumulation technique is already proven itself to be a powerful tool in obtaining thick (50 µm) tissues and its main advantage is the rapid production of tissues and its ease of performance. However, the applied combination yields tissue thicknesses that are doubled, which is of outstanding importance for an improved handling of the scaffolds and the generation of clinically relevant sample volumes. Moreover, a correlation of increasing vascular endothelial growth factor secretion to hypoxic conditions with increasing pore sizes and an assessment of the formation of neovascular like structures are included.     

In-situ resource utilisation manufacturing of optically transparent glass from lunar regolith simulant

Journal of Materials Science - International space agencies are aiming to establish permanent outposts on the lunar surface. For that purpose, new technologies and equipment are being developed...     

亚洲洗涤习惯与衣物白度的保持

荧光增白剂会在使用过程中被清洗或降解掉,其常规性更新换代促使白色织物越来越被人们所接受.由于白色织物的种类和洗涤习惯都存在着千差万别,很难定义一种最为行之有效的荧光增白剂配方,既能提供高效的增白效果,又不具有不可逆地破坏织物外观的威胁.通过预测白度在反复的洗涤和日晒过程中可能发生的变化,可以得到一种减小风险的新方法.这个模型的基础是来源于不同地区的白色织物的基本数据,光照数据和评价一切与白度相关的因素的各种工具.     

Multimodal Bioactivation of Hydrophilic Electrospun Nanofibers Enables Simultaneous Tuning of Cell Adhesivity and Immunomodulatory Effects

Biomaterials research usually focuses on functional and structural mimicry of the extracellular matrix or tissue hierarchy and morphology. Most recently, material‐induced modulatory effects on the immune system to arouse a healing response is another upcoming strategy. Approaches, however, that integrate both aspects to induce healing and facilitate specific cell adhesion are so far little explored. This study exploits manifold but chemical crosslinker free functionalization of hydrophilic and nonadhesive electrospun fiber surfaces with peptides for controlled cell adhesion, and with neutra­lizing antibodies targeting the master cytokine tumor necrosis factor (TNF) to dampen proinflammatory reactions by the fiber adherent cells. It is demonstrated that cell attachment and immunomodulatory properties of a textile can be tailored at the same time to generate meshes that combine immunosuppressive activity with specific cell adhesion properties.     

Structural Elucidation of a Nonpeptidic Inhibitor Specific for the Human Immunoproteasome

Selective inhibition of the immunoproteasome is a promising approach towards the development of immunomodulatory drugs. Recently, a class of substituted thiazole compounds that combine a nonpeptidic scaffold with the absence of an electrophile was reported in a patent. Here, we investigated the mode of action of the lead compound by using a sophisticated chimeric yeast model of the human immunoproteasome for structural studies. The inhibitor adopts a unique orientation perpendicular to the β5i substrate‐binding channel. Distinct interactions between the inhibitor and the subpockets of the human immunoproteasome account for its isotype selectivity.     

Ultralow loading Pt nanocatalysts prepared by atomic layer deposition on carbon aerogels

Using atomic layer deposition (ALD), we show that Pt nanoparticles can be deposited on the inner surfaces of carbon aerogels (CA). The resultant Pt-loaded materials exhibit high catalytic activity for the oxidation of CO even at loading levels as low as approximately 0.05 mg Pt/cm2. We observe a conversion efficiency of nearly 100% in the 150-250 degrees C temperatures range, and the total conversion rate seems to be limited only by the thermal stability of the CA support in ambient oxygen. The ALD approach described here is universal in nature, and can be applied to the design of new catalytic materials for a variety of applications, including fuel cells, hydrogen storage, pollution control, green chemistry, and liquid fuel production.     

COMT genetic variation affects fear processing: Psychophysiological evidence.

Emotional dysregulation is a core characteristic of many psychiatric diseases, including the anxiety disorders. Although heritable influences account for a significant degree of variation in risk for such disorders, relatively few candidate susceptibility factors have been identified. A coding variant in one such gene, encoding the dopamine catabolic enzyme catechol-O-methyltransferase (COMT Val158Met), has previously been associated with anxiety and with anxiety-related temperament and altered neural responses to affective stimuli in healthy individuals. In 96 healthy women recruited from a sample of 800 participants according to genotype, the authors tested for an association between the DRD2/ANKK1 Taq Ia, the COMT Val158Met, and a psychophysiological measure of emotion processing, the acoustic affective startle reflex modulation (ASRM) paradigm, and found that COMT genotype significantly affected startle reflex modulation by aversive stimuli, with Met158 homozygotes exhibiting a markedly potentiated startle reflex compared with Val158 carriers. A trait measure of anxiety (Gray's Behavioral Inhibition System; J. A. Gray & N. McNaughton, 2000) was also associated with ASRM. The functional polymorphism in the dopamine D2 receptor (DRD2/ANKK1 Taq Ia) had no effect on startle modulation. The findings support prior genetic and neuroimaging associations of the COMT 158Met allele to affective psychopathology and alterations in neural systems for emotional arousal and regulation. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Development of a computer-assisted high-pressure Injection device for vertebroplasty

A novel computer-assisted injection device for the delivery of highly viscous bone cements in vertebroplasty is presented. It addresses the shortcomings of manual injection systems ranging from low-pressure and poor level of control to device failure. The presented instrument is capable of generating a maximum pressure of 5000 kPa in traditional 6-ml syringes and provides an advanced control interface for precise cement delivery from outside radiation fields emitted by intraoperative imaging systems. The integrated real-time monitoring of injection parameters, such as flow-rate, volume, pressure, and viscosity, simplifies consistent documentation of interventions and establishes a basis for the identification of safe injection protocols on the longer term. Control algorithms prevent device failure due to overloading and provide means to immediately stop cement flow to avoid leakage into adjacent tissues.