The effects of blackcurrant and strawberry powder on the physicochemical and in vitro glycaemic response of starches derived from sweet potato (Ipomoea batatas) and potato (Solanum tuberosum)

Phenolic compounds have been shown to deliver numerous health benefits. Research has also shown that starch and phenolic compounds interact. This study aimed to investigate the effects of blackcurrant and strawberry powder on the physicochemical and in vitro predicted glycaemic response of sweet potato and potato starches. Sweet potato, or potato, starches were mixed with 0%, 5%, 10% and 15% (w/w) of blackcurrant, or strawberry, powder, to form blackcurrant and strawberry-enriched starch pastes. The results showed that enrichment with 5%, 10% and 15% blackcurrant or strawberry powder for sweet potato and potato starch significantly altered the pasting viscosity and colour profiles (P < 0.05), increased the phenolic content and antioxidant activities of starch pastes (P < 0.05). Blackcurrant or strawberry powders mixed with sweet potato or potato starches reduced amount of reducing sugar released during in vitro digestion. Addition of 15% blackcurrant powder for the starch exerted stronger in vitro antioxidant and hypoglycaemic properties than that of 15% strawberry powder. Collectively, these findings suggested that addition of blackcurrant or strawberry powder into sweet potato and potato starches manipulated the hypoglycaemic property of pastes.     

Encapsulation and characterisation of grape seed proanthocyanidin extract using sodium alginate and different cellulose derivatives

Grape seed proanthocyanidin extract (GSPE) has health benefits. However, these phenolic compounds undergo degradation reactions and have undesirable sensorial characteristics. GSPE was encapsulated using sodium alginate (SA), SA-methyl cellulose (MC) and SA-hydroxypropyl methylcellulose (HPMC) for promoting controlled release, pH stability, temperature and storage period tolerance of GSPE. The microcapsules were characterised using scanning electron microscopy (SEM) and Fourier transform infra-red (FTIR) analysis. The SA-MC and SA-HPMC microcapsules appeared to have a more compact surface than SA-alone microcapsules. FTIR analysis indicated successful immobilisation of GSPE into the polymeric microcapsules. Moreover, the SA-MC and SA-HPMC microcapsules showed higher thermal stability. The microcapsules showed a relatively higher amount of released GSPE at a pH above six than at a lower pH. The SA-MC and SA-HPMC microcapsules could be used to retain more GSPE content in the gastric phase and to release it in the intestinal phase for possible absorption. Furthermore, after 28 days of storage at 25 °C, the GSPE retention rate of the microcapsules was still higher than 80%. GSPE encapsulated in SA-MC and SA-HPMC microcapsules results in lesser degradation and can be absorbed more effectively. This method has potential for the delivery of colon-specific materials while exhibiting a sustained-release characteristic.     

An Organoid for Woven Bone

Bone formation (osteogenesis) is a complex process in which cellular differentiation and the generation of a mineralized organic matrix are synchronized to produce a hybrid hierarchical architecture. To study the mechanisms of osteogenesis in health and disease, there is a great need for functional model systems that capture in parallel, both cellular and matrix formation processes. Stem cell-based organoids are promising as functional, self-organizing 3D in vitro models for studying the physiology and pathology of various tissues. However, for human bone, no such functional model system is yet available. This study reports the in vitro differentiation of human bone marrow stromal cells into a functional 3D self-organizing co-culture of osteoblasts and osteocytes, creating an organoid for early stage bone (woven bone) formation. It demonstrates the formation of an organoid where osteocytes are embedded within the collagen matrix that is produced by the osteoblasts and mineralized under biological control. Alike in in vivo osteocytes, the embedded osteocytes show network formation and communication via expression of sclerostin. The current system forms the most complete 3D living in vitro model system to investigate osteogenesis, both in physiological and pathological situations, as well as under the influence of external triggers (mechanical stimulation, drug administration).     

不同安装角度对重介质旋流器内流场的分析研究

由于影响重介质旋流器流场的几何参数较多,针对性地研究不同旋流器安装角度对重介质旋流器流场的影响,进而降低煤炭运输和处理灰分的生产成本,实现煤炭的清洁,从而提高煤炭的质量.     

基于特征融合的主观题智能阅卷算法研究

为了实现主观题智能阅卷,本文提出了一个基于多特征融合的主观题智能阅卷算法.首先,分别设计两种算法:关键词相似度算法和语义相似度算法,计算学生答案和标准答案之间的关键词相似度和语义相似度;然后,以题目的 题型和科目作为特征值,分别计算出两相似度的权值,并利用权值计算出学生答案的得分实验表明,本文提出的算法,能有效主观题智能阅卷算法的准确性,具有较好的应用前景.     

火成岩发育区钻井液技术研究与应用

渤海某油田古近系发育火成岩,且火成岩的发育情况差异较大.水敏性火成岩地层存在很多情况,如安全钻井周期短,钻井作业过程中易出现憋压、蹩扭矩、井眼坍塌、卡钻、出新井眼等复杂情况,事故频发.针对此类情况,形成以"物理+化学"井壁固化技术及PF-AquaTrol高效抑制剂协同盐类的综合抑制技术为主的高性能水基钻井液技术,达到井壁稳定的效果,延长安全钻井周期,提高生产时效,平均生产时效提高10％,倒划眼时效提高70％.     

A Hydro-Economic Model for Optimizing Management of Mine Water: A Case Study in the Suancigou Coal Mine,Northwestern China

Mine Water and the Environment - Comprehensive analysis of hydrogeological conditions at a typical coal mine in northwestern China allowed us to establish a groundwater numerical model, which we...