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The present study aims at investigation on the morphology, rheology, isothermal crystallization and foaming behavior of the fibrillated PCL/PLA composites. The samples containing 5, 10 and 20 wt% PLA were melt-blended with PCL using a twin-screw extruder, following hot-stretching. The SEM morphology results revealed that the samples before stretching demonstrated spherical PLA domains; however, after stretching the spherical particles transformed to fibrillar structures and developed a 3D-network of entangled PLA fibers. Melt rheological properties of the samples before stretching suggested that the viscosity and storage modulus of the composites were increased with increasing the amount of PLA particles. This effect became more noticeable when the PLA domains were fibrillar. Moreover, rheological results unveiled that the fibrillated PCL/PLA composites showed a solid-like behavior which was evidenced with a plateau of storage modulus at low frequency region. Isothermal crystallization kinetics of the composites indicated that the PLA nanofibrils acting as heterogeneous nucleation, remarkably accelerated the crystallization at various crystallization temperature. Moreover, under high PLA nanofirbrils, the interaction between a large amout of induced PCL crystal nuclei and increased viscosity hinder motion of PCL molecules, which resulted in a higher isothermal crystallization activation energy. A close examination of batch foaming data suggested that the fibrillated samples induced further open-cell foams in comparison with that of the pure PCL and undrawn PCL/PLA samples.

A new economical applied method has been developed to modify the polylactic acid (PLA) and acrylonitrile butadiene styrene (ABS) immiscible blends. The different molecular weights of polyethylene glycol (PEG) were adopted during processing. The morphology of PLA/ABS blends was successfully controlled by 10 wt% content of PEG, and the morphology results show remarkable changes at the PLA/ABS blend interface. A fluctuation of the storage modulus at the frequency lower than 0.1 rad/s of PLA/PEG/ABS blends also reflects the structure change in the system. The mechanical properties as well as the thermal and decomposition properties of the modified blends improve with increasing molecular weight of PEG. All the results of properties indicate that the interaction of polymer blend molecular chain decreases and the processability of the PLA/ABS blends increase both due to the addition of PEG.

During the regeneration of tissues and organs, growth factors (GFs) play a vital role by affecting cell behavior. However, because of the low half-life time and quick degradation of GFs, their stimulations on cells are relatively short and discontinuous. In this study, a releasing scaffold platform, consisting of polycaprolactone (PCL) nanofibers and vascular endothelial growth factor (VEGF)-encapsulated gelatin particles, was developed to extend the influence of GFs on mesenchymal stem cells (MSCs) and endothelial cells (ECs). The results showed that this kind of scaffold can direct the differentiation of MSCs to ECs and maintain the stability of the tubular structure, an indicator of the angiogenesis ability of ECs, for an extended period of time. Therefore, the results suggest the potential application of PCL/VEGF-encapsulated gelatin particles (PCL/VGPs) as a growth factor (GF)-releasing scaffold platform in vascular tissue engineering.

Organic agriculture world-wide offers the promise of a future to produce and distribute food and other farm products in a healthy, ecologically sound, truly sustainable and fair way. The full benefits of organic agriculture are just now being realized—from ecosystem services to the provision of healthier food - yet, to reach its full potential organic farming needs to address many challenges. While organic agriculture has grown in strength and is in the most favorable position it has ever been in with respect to market conditions, government policies and international institutional support, it still does not have adequate resources to continue its expansion. The Technology Innovation Platform of IFOAM (TIPI) has developed a vision and an agenda to advance organic agriculture through research, development, innovation and technology transfer. TIPI’s vision recognizes that current technologies based on heavy use of external inputs that are toxic and pollute the environment come with a price. Investments in ecosystem services and the development of technologies that are productive, stable, adaptable, resilient, and fairly shared are much more likely to sustain the world’s population in a rapidly changing environment. Sustainable pathways to innovation will require engagement of all stakeholders in a science driven multi-disciplinary approach. Such an approach seeks to (1) Empower rural areas, (2) Provide eco-functional intensification that produces food and ecosystem services, and (3) Provide food for the health and well-being available to all. Organic agriculture must build the capacity to fulfill the world’s food needs for the entire population if it is to fulfill its mission. The new paradigm proposed by TIPI is founded upon a whole systems approach, the engagement of farmers, researchers and other practitioners in a co-innovative approach; and open access technologies that are readily adapted to local conditions. While there are barriers and bottlenecks that will need to be overcome for this vision to be realized, TIPI calls upon the organic community to support its 14 point action plan to advance organic agriculture in a forward-thinking and innovative way.

With the rapid development of international production and trade in organic food, organic agriculture is also boosting in China. The milestone of Chinese organic agri-culture was set in 1990 with the first export of a certified organic product (tea) from Lin’an county of Zhejiang Province, China, which marked the launch of organic pro-duction in China. By the end of 2005, there had been about 4.384 million ha organic land, including 1.694 million ha organic, 0.61 million ha conversion as well as 2.08 million ha collection area, about half of which is certified area. About 4.93 million tons organic products and nearly 1600 projects had been certified with 300~400 varieties. According to the above data, now China ranks the 3rd largest country of organic production in the world. In China, organic development mostly is export oriented, the export products include beans, rice, tea, mushroom, vegetable, processed oil and herbs, etc. According to the certifying body COFCC of Ministry of Agriculture (MOA), the value of exported organic products increased from 0.3 million USD in 1995 to 0.35 billion USD at the end of the year 2004. Chinese domestic organic market started from 2000. Presently, most of the products sold in domestic markets are certified by COFCC and OFDC in some largest cities such as Beijing, Shanghai, Guangzhou, Nanjing and Shenzhen, etc. The price of the organic products is often up to 3 times the price of conventional products. Average organic food consumption accounts for 0.08% of the conventional food (LI 2006).