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保暖服更小的体积，帐篷和睡眠包也能具有同样的优势，家用冰箱和使用其他形式的材料进行绝缘的冰箱壁会在厚度上收缩，进而来提高它的存储容量，Meador说道这种水凝胶的效率值要比现存绝缘材料高5到10倍，而且在拥有四分之一英尺厚度的薄片的条件下能够提供3英尺纤维玻璃的绝缘性，因此，这种薄且高效的绝缘材料在建筑、管道、热水器和其他设备中具有多重应用。
NASA预测其中一项应用是在从国际空间站返回到地球的航天器的高级再入系统，再入车辆需要一个使它们避免烧起来（由于地球大气的摩擦加热）的防热罩，这些防护罩体积庞大而且很笨重，所以NASA正在研究一种由柔软气凝胶制成的热力防护盾，这种气凝胶在航天器进入到大气层中时会像气球一样膨胀。
Meador说道这种材料还可以被用来使航空服绝缘，然而，它很可能不太适用于消防服装产品——它需要超过气凝胶限制575华氏度的保护。
科学家在两天的时间内生产出了更坚硬的新型气凝胶，其中一个步骤是改变了传统硅基气凝胶的内部构造，他们使用一种聚合物（一种塑料状的材料）来加强通过气凝胶结构进行扩展的硅的网格，另一个步骤是利用聚酰亚胺（一种极强的抗热聚合物，或者说是塑料状材料）来制造气凝胶，然后嵌入支柱状的交叉连接来进一步提高这个结构的强度。
Organic & Polymer（有机高分子材料）
Biocompatible cellulose nanostructures could speed wound recovery
Wound healing is a complicated process consisting of several different phases and a delicate interaction between different kinds of cells, signal factors and connective tissue substance. If the wound healing does not function optimally, this can result in chronic wounds, cicatrisation or contractures. By having an optimal wound dressing such negative effects can be reduced. A modern wound dressing should be able to provide a barrier against infection, control fluid loss, reduce the pain during the treatment, create and maintain a moist environment in the wound, enable introduction of medicines into the wound, be able to absorb exudates during the inflammatory phase, have high mechanical strength, elasticity and conformability and allow for easy and painless release from the wound after use.
Nanocellulose is a highly fibrillated material, composed of nanofibrils with diameters in the nanometer scale (< 100 nm), with high aspect ratio and high specific surface area. Cellulose nanofibrils have many advantageous properties, such as high strength and ability to self-assembly.
Recently, the suitability of cellulose nanofibrils from wood for forming elastic cryo-gels has been demonstrated by scientists from Paper and Fibre Research Institute (PFI) in Norway and Lund University.. Cryogelation is a technique that makes it possible to engineer 3-D structures with controlled porosity. A porous structure with interconnected pores is essential for use in modern wound healing in which absorption of exudates, release of medicines into the wound or exchange of cells are essential properties.
Recently, the NanoHeal project has been granted funding by the Norwegian Research Council of Norway, through the Nano2021 program. In the NanoHeal project cryogelation will be one of the methods for engineering porous composite materials based on nanocellulose from wood. Such porous materials will be the basis for the development of advanced materials for wound healing.
The NanoHeal project is multi-disciplinary and has a wide cooperation between scientists and industry with competence within material technology, biotechnology, wound microbiology, biomaterials, pharmaceutics and 36
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medicine. The active partners are located in four European Universities, Norwegian University of Science and Technology (Dept. of medicine), Cardiff University, Swansea University and Lund University. In addition, the NanoHeal project has the support of a Norwegian industrial partner (AlgiPharma), a biopharmaceutical company having wound healing as one of their primary focus areas.
The manager of the NanoHeal project will be senior researcher Gary Chinga Carrasco at PFI, Paper and novel materials. PFI is a centre of expertise for wood fibres, paper, new biobased materials and sustainable biorefining. The project period is between 2012 and 2016.
生物兼容性纤维素纳米结构能够加速伤口的愈合
伤口的愈合是一个非常复杂的过程，这个程序包含了几种不同的阶段和不同类型细胞、信号因素和结缔组织物质之间微妙的交互作用。如果伤口愈合不能有效的起作用，那么就会引起慢性的损伤、痉挛或挛缩，通过使用一种理想的伤口敷料，这种负面效应能够被降低，一种现代的伤口敷料能够有效的抵抗感染，控制体液损失，在治疗的过程中降低疼痛，在伤口周围形成一个湿润的环境，并使药物能够直接作用到伤口上，从而在炎症阶段有效的吸收渗出物，产生较高的机械强度、弹性和适应性，并在使用完以后很容易并无痛的从伤口中释放出来。
纳米纤维素是一种高度富含原纤维组织的材料，它是由直径在毫微米级（< 100 nm）的微纤丝构成的，且具有较高的长宽比和比表面积，纤维素微纤丝具有许多有益的特性，例如高强度和自动组装的能力。
最近，木材中的纤维素微纤丝在形成弹性低温胶时的适应性被来自挪威Paper and Fibre Research Institute (PFI)和隆德大学的科学家进行了证明。低温胶合是一种能够设计带有可控多孔性的3D结构的技术，带有相互连接的气孔的多孔结构对于现代伤口愈合（在这个过程中渗出液的吸收以及药物在伤口上的释放和细胞的交换都是重要的特性）的应用来说是必需的。
最近，一个纳米愈合项目被Norwegian Research Council of Norway研究委员会提供了资助，通过Nano2021计划。在纳米愈合项目中，低温凝胶是基于木材中的纳米微纤丝设计多孔复合材料的一种方法，这种多孔材料是为伤口愈合开发高级材料的基础。
纳米愈合项目是一个多学科的研究领域，并且包含了科学家和在材料技术、生物技术、伤口微生物、生物材料、配药学和医药学等领域进行竞争的产业之间的合作，这些积极的合作伙伴包括四个欧洲大学、挪威科技学院、卡迪夫大学、斯旺西大学和瑞典兰德大学。此外，纳米愈合项目还获得了一个挪威工业伙伴、一家生物制药学公司的支持。
纳米愈合项目的项目负责人是PFI纸张和新型材料研究所的高级研究员Gary Chinga Carrasco，PFI是一个专门研究木制纤维、纸张、新型生物基材料和可持续性生物提炼的研究中心，这个项目的起止日期是2012年到2016年。
Biomimetic Fibrous Scaffolds for Tissue Engineering
Tissue engineers aim for individual and functional tissue substitutes. Ensuring vitality is of critical importance: the substitute should integrate into the surrounding tissue and feature the tissue‘s normal biological functionalities; that is, it should be able to grow and regenerate along with the natural tissue. Usually, the artificial tissue is generated in vitro, being implanted into the patient at a later stage.
Biomimetic scaffolds for cellular growth need to be enzyme-degradable and biocompatible, but water-resistant at the same time to prevent a decrease in the scaffold strength due to random hydrolysis.They have to efficiently mimic the extracellular matrix in order to favor cell attachment and growth without inducing an immune response. Although synthetic polymers like poly(lactic acid) (PLLA) are usually less immunogenic and more flexible than
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natural polymers, they often lack hydrophilicity and natural recognition sites. Native poly(g-glutamic acid) (g-PGA), a polyamino acid derived from microbial origin, is composed of D-and L-glutamic acid units. Its use is limited by its polyanionic nature and high water solubility, but it allows for facile modification of its chemical handles and conjugation of functional entities to the side-chains.
Researchers from Imperial College, London, have now developed a series of modified g-PGA polyester scaffolds for tissue engineering applications. They report that esterified g-PGA-Et, g-PGA-Pr, and g-PGA-Bn exhibit unique advantages over g-PGA in terms of water-resistance, cell adhesion, and cell viability. Biomimetic fibrous scaffolds with a 3D matrix architecture are produced by electrospinning of the biocompatible polymer to sub-micrometer fibers. It is observed that the esters of increasing hydrophobicity are water-resistant and non-cytotoxic, but g-PGA-Bn shows the best performance as far as cell adhesion and viability (without an increase in protein adsorption)are concerned.
The co-modification of g-PGA-Bn with an integrin-binding RGD peptide (GRGDY) provides a scaffold with similar potential as g-PGA-Bn. If the cells are pre-incubated with GRGDY, a decrease in cell adhesion is noticed for the g-PGA-Bn-GRGDY scaffolds only.
Therefore, the authors conclude that aromatic functionality plays a crucial role in the regulation of cell adhesion behavior and that the cell scaffold interactions are not essentially governed by RGD-binding integrins. In addition they successfully design and produce new scaffolds based on enzyme-degradable and non-cytotoxic g-PGA which support adhesion, differentiation, and proliferation of hMSCs (human mensenchymal stem cells) for tissue engineering purposes with an improved performance compared with conventional PLLA.
为组织的建造开发出的仿生物纤维支架
组织工程师通常会把单个的功能性组织替代品作为目标，确保生命力也非常重要：替代品应该能够融入到周围的组织中，并具有组织的正常生物功能，也就是说，它应该能够生长并跟自然组织一起进行再生，一般来说，这种人造组织会在体外被生产出来，并在接下来的步骤中被移植到病人体内。
细胞生长的仿生物支架需要具有酶降解和生物相容性，但是抗水性同时也会阻止支架强度的下降，由于随机的水解作用，他们必须能够有效的模拟细胞外基质，以便在不引起免疫反应的条件下支持细胞的附着和生长。
尽管例如聚乙烯的合成聚合物通常会比自然聚合物更灵活且具有更小的免疫产生性，它们缺乏亲水性和自然识别位置。天然的聚乙烯（g-谷氨基酸）(g-PGA)——一种从微生物中派生出的聚氨基酸——是由D-和L-谷氨基酸组成的，它的使用受到了它的聚阴离子特性和高水溶性的限制，但是它的化学控键和边链功能实体的配置很容易进行修改。
目前，来自伦敦帝国理工学院的研究者为组织设计应用开发出了一系列修改后的g-PGA聚酯支架，他们报告称酯化的g-PGA-Et, g-PGA-Pr和g-PGA-Bn跟g-PGA相比在抗水性、细胞粘度和细胞生存性方面具有独特的优势，具有3D矩阵结构的仿生纤维支架是被生物相容的聚合物到次微米纤维的静电纺丝生产出来的，他们观察到疏水性不断提高的酯类具有抗水性并且不含细胞毒素，但是就细胞粘度和生存能力而言g-PGA-Bn展示出了最佳性能。
g-PGA-Bn和一种整合素束缚的RGD缩氨酸的协同修改提供了一个具有像g-PGA-Bn的类似潜能的支架，如果细胞能够通过GRGDY进行预培养，那么细胞粘度的下降就会在g-PGA-Bn-GRGDY支架中显示出来。
因此，作者总结道芳香植物的功能在细胞粘度习性的整合过程中起到了关键的作用，并且细胞支架的交互作用从根本上来说不会被RGD附着的整合素所控制，此外，他们还基于酶降解和不含细胞毒素的g-PGA（它支持hMSCs为组织设计的目的而进行的粘结、变异和增殖，并且跟传统的PLLA相比它具有改良性的功能）成功的设计和生产出了新的支架。
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Behaviors of the Tiniest Water Droplets Revealed
A new study by researchers at the University of California, San Diego, and Emory University has uncovered fundamental details about the hexamer structures that make up the tiniest droplets of water, the key component of life -- and one that scientists still don't fully understand.
The research, recently published in The Journal of the American Chemical Society (JACS), provides a new interpretation for experimental measurements as well as a vital test for future studies of our most precious resource. Moreover, understanding the properties of water at the molecular level can ultimately have an impact on many areas of science, including the development of new drugs or advances in climate change research.
\Paesani, one of the paper's corresponding authors who is an assistant professor in the Department of Chemistry and Biochemistry at UC San Diego and a computational researcher with the university's San Diego Supercomputer Center (SDSC). \water, proteins don't work and life as we know it wouldn't exist. Understanding the molecular properties of the hydrogen bond network of water is the key to understanding everything else that happens in water. And we still don't have a precise picture of the molecular structure of liquid water in different environments.\
Researchers know that the unique properties of water are due to its capability of forming a highly flexible but still dense hydrogen bond network which adapts according to the surrounding environment. As described in the JACS paper, researchers have determined the relative populations of the different isomers of the water hexamer as they assemble into various configurations called 'cage', 'prism', and 'book'.
The water hexamer is considered the smallest drop of water because it is the smallest water cluster that is three dimensional, i.e., a cluster where the oxygen atoms of the molecules do not lie on the same plane. As such, it is the prototypical system for understanding the properties of the hydrogen bond dynamics in the condensed phases because of its direct connection with ice, as well as with the structural arrangements that occur in liquid water. This system also allows scientists to better understand the structure and dynamics of water in its liquid state, which plays a central role in many phenomena of relevance to different areas of science, including physics, chemistry, biology, geology, and climate research. For example, the hydration structure around proteins affects their stability and function, water in the active sites of enzymes affects their catalytic power, and the behavior of water adsorbed on atmospheric particles drives the formation of clouds.
\chemistry, meaning molecules made of five monomers) but the energetic ordering of the low-lying isomers of the hexamer has always been controversial,\
Added corresponding author Joel M. Bowman, with Emory University's Department of Chemistry and the Cherry L. Emerson Center for Scientific Computation: \are the first simulations that use an accurate, full-dimensional representation of the molecular interactions and exact inclusion of nuclear quantum effects through state-of-the-art computational approaches. These allow us to accurately determine the stability of the different isomers over a wide range of temperatures ranging from 0 to 150 Kelvin, (almost minus 460 degrees to about minus 190 degrees Fahrenheit).\
While the prism isomer was identified as the global minimum-energy structure, the quantum simulations predicted that both the cage and prism isomers are present in nearly equal amounts at extremely low temperatures, researchers found. As the temperature increased, more cages, and then book structures, began to appear.
Researchers used SDSC's new data-intensive Gordon supercomputer as well as SDSC's Triton compute cluster to conduct the data-intensive simulations.
\Volodymyr Babin, a researcher with UC San Diego's Department of Chemistry and Biochemistry. \
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