分形城市、空间私有与NKS

建筑与城市,在我们可见的未来几十年里,会走向何方呢? 有两个命题或许将成为主流: 一个是数字化、网络化对城市及建筑的影响.从这个意义上来说,建筑和建筑师都在被迫做减法.因为他们的功能都在逐一溶解,建筑从类型明确的格局走向它的最初--遮蔽与隔断;建筑师则从一技之能的专家返回到人手可及的工匠.     

Can Natural Products Exert Neuroprotection without Crossing the Blood–Brain Barrier?

The scope of evidence on the neuroprotective impact of natural products has been greatly extended in recent years. However, a key question that remains to be answered is whether natural products act directly on targets located in the central nervous system (CNS), or whether they act indirectly through other mechanisms in the periphery. While molecules utilized for brain diseases are typically bestowed with a capacity to cross the blood–brain barrier, it has been recently uncovered that peripheral metabolism impacts brain functions, including cognition. The gut–microbiota–brain axis is receiving increasing attention as another indirect pathway for orally administered compounds to act on the CNS. In this review, we will briefly explore these possibilities focusing on two classes of natural products: omega-3 polyunsaturated fatty acids (n-3 PUFAs) from marine sources and polyphenols from plants. The former will be used as an example of a natural product with relatively high brain bioavailability but with tightly regulated transport and metabolism, and the latter as an example of natural compounds with low brain bioavailability, yet with a growing amount of preclinical and clinical evidence of efficacy. In conclusion, it is proposed that bioavailability data should be sought early in the development of natural products to help identifying relevant mechanisms and potential impact on prevalent CNS disorders, such as Alzheimer’s disease.     

Effects of fines and water contents on the mechanical behavior of interlayer soil in ancient railway sub-structure

In the ancient railway sub-structure in France, after years of operation, the inter-penetration of fine particles of sub-grade and ballast has created a new layer referred to as the interlayer. As it was naturally formed, the fines content and water content of the interlayer vary considerably. In this study, the effects of the fines and water contents on the mechanical behavior of interlayer soil were investigated by carrying out large-scale monotonic and cyclic triaxial tests. The results of the monotonic triaxial tests show that adding more fines in the interlayer soil does not significantly change the shear strength in the dry condition (water content w=4% and 6%), but drastically decreases the shear strength parameters (friction angle and cohesion) in the nearly saturated condition (w=12%). The cyclic triaxial tests were performed at various deviator stress levels. By considering the permanent axial strain at the end of application of each stress level, it was found that the higher the fines content in the nearly saturated condition (w=12%), the larger the permanent axial strain. In the case of lower water content (w=4% and 6%), the opposite trend was identified: adding fines decreases the permanent axial strain.     

Spray and freeze drying of human milk on the retention of immunoglobulins (IgA,IgG, IgM)

Several freeze-drying and spray-drying methods were investigated in relation to the retention of immunoglobulins (Ig) A, IgG, and IgM. Spray drying produced human milk powders with 2% humidity and a good retention of IgG (>88%) and IgM (～70%). However, only 38% of IgA remained after spray drying. For freeze drying, only the highest heating plate temperature used in this study (40°C) brought IgA content down to 55% in powder with 1.75% residual humidity, whereas milk samples undergoing lower temperatures had higher preservation rates (75% for IgA and 80% for IgG and IgM) and higher residual moisture contents. From these results, it can be concluded that IgA is the most sensitive Ig lost during drying processing of human milk. The best method to generate human milk powders without a significant loss of Ig was thus freeze drying at 30°C heating plate temperature, which accelerated the process compared to lower processing temperatures, but still had good overall Ig retention.