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1.
The objective of this study was to characterise the nutritional potential of leaves and identify a diversity centre with low cyanide and high nutrient content among 178 Latin American cassava genotypes. This field-based collection represents the seven diversity centres, held at The International Center for Tropical Agriculture (CIAT Palmira, Colombia) by the Cassava Program. The cyanide, all-trans-β-carotene and lutein concentrations in cassava leaves ranged from 346 to 7484 ppm dry basis (db), from 174–547 μg g−1 db and 15–181 μg g−1 db, respectively. Cassava leaves also showed significant levels of essential amino acids leucine, lysine, phenylalanine, valine and threonine, and average total protein content of 26.24 g 100 g−1 db. Among seven diversity centres, South American rainforest group showed low cyanide and high carotene content in leaves. In addition, VEN77 and PAN51 genotypes stood out for having low cyanide in leaves and roots and high carotene in leaves. This genetic diversity can be used to select high potential progenitors for breeding purposes.  相似文献   
2.
Spirituality is a critical component of the holistic mind-body-spirit model embraced by Hospice. Hospice chaplains, as part of the caregiving team, must understand their abilities and limitations in providing spiritual guidance to others who may differ in religious and spiritual beliefs.  相似文献   
3.
Spirulina (Arthrospira), a filamentous, unicellular alga, is a cyanobacterium grown in certain countries as food for human and animal consumption. It is also used to derive additives in pharmaceuticals and foods. This alga is a rich source of proteins, vitamins, amino acids, minerals, and other nutrients. Its main use, therefore, is as a food supplement. Over the last few years, however, it has been found to have many additional pharmacological properties. Thus, it has been experimentally proven, in vivo and in vitro that it is effective to treat certain allergies, anemia, cancer, hepatotoxicity, viral and cardiovascular diseases, hyperglycemia, hyperlipidemia, immunodeficiency, and inflammatory processes, among others. Several of these activities are attributed to Spirulina itself or to some of its components including fatty acids omega-3 or omega-6, beta-carotene, alpha-tocopherol, phycocyanin, phenol compounds, and a recently isolated complex, Ca-Spirulan (Ca-SP). This paper aims to update and critically review the results published over the last few years with regards to these properties. The conclusion is that even if this cyanobacterium has been one of the most extensively studied from the chemical, pharmacological and toxicological points of view, it is still necessary to expand the research in order to have more consistent data for its possible use in human beings.  相似文献   
4.
The design and management of firewall rule sets is a very difficult and error-prone task because of the difficulty of translating access control requirements into complex low-level firewall languages. Although high-level languages have been proposed to model firewall access control lists, none has been widely adopted by the industry. We think that the main reason is that their complexity is close to that of many existing low-level languages. In addition, none of the high-level languages that automatically generate firewall rule sets verifies the model prior to the code-generation phase. Error correction in the early stages of the development process is cheaper compared to the cost associated with correcting errors in the production phase. In addition, errors generated in the production phase usually have a huge impact on the reliability and robustness of the generated code and final system.In this paper, we propose the application of the ideas of Model-Based Development to firewall access control list modelling and automatic rule set generation. First, an analysis of the most widely used firewall languages in the industry is conducted. Next, a Platform-Independent Model for firewall ACLs is proposed. This model is the result of exhaustive analysis and of a discussion of different alternatives for models in a bottom-up methodology. Then, it is proposed that a verification stage be added in the early stages of the Model-Based Development methodology, and a polynomial time complexity process and algorithms are proposed to detect and diagnose inconsistencies in the Platform-Independent Model. Finally, a theoretical complexity analysis and empirical tests with real models were conducted, in order to prove the feasibility of our proposal in real environments.  相似文献   
5.
This paper reviews offshore wind projects with a wide perspective. The current situation of the offshore wind market is presented, pointing out the countries leading the process in terms of installed capacity and in terms of technological leadership. Feasibility studies of alternative offshore wind farms (OWFs) are interesting not only in relation to the business but in relation to the techno-economical analyses that engineering researchers need to do. Details about the average energy yield assessment, the costs and the price for the purchased energy are commented on, as key elements of those feasibility studies. The higher cost of renewable energy sources of electricity (RESE) when compared with conventional sources, demands appropriate policy support. The European regulatory framework and the support schemes established by European Member States are presented, as well as the role that different transmission system operators (TSOs) are playing at the moment. Finally, most of the OWFs currently operating are presented, analysing the technical characteristics of their electric subsystems: the wind energy conversion systems (WECSs) transforming the kinetic energy of the wind into electricity, the collector system (CS) gathering the power output of all the turbines to a central collection point (CCP) and the transmission system (TS) taking that power to the onshore main grid.  相似文献   
6.
Understanding retention of carotenoids after different processing methods is important. This study was conducted to quantify dry matter content and carotenoids found in different sections of the cassava roots from six clones and to assess true retention of carotenoids after 30 min of boiling. Retention was quantified in normalized prisms taken from proximal, central and distal sectors of the root. Dry matter content (DMC) was measured along and across the roots and varied from 14.1 to 51.0%. DMC tended to be lower at the center of the root and in distal sections. DMC affected the homogeneity of the food matrix and, therefore, contributed in spatial variation in retention of carotenoids. Average true retention (dry matter basis) was 86.6% and ranged from 76.0 and 96.7% (averages per clone and section of the root, respectively). Retention was positively associated with carotenoid content in unprocessed samples, although the relationship was weak. The study shows that during boiling weight of samples changed from slight losses to gains of up to 40% (depending on original DMC of the uncooked root), resulting in an “apparent dilution” of the carotenoids. Results suggested the occurrence of some isomerization. All-trans β-carotene losses (13%) were partially explained by increases in the 13-cis (34%) and 15-cis (8%) isoforms, as well as lixiviation (< 1%) into the boiling water.  相似文献   
7.
What factors help and hinder creativity within the strategic planning process? An exploratory study examined the strategic plans of groups of graduates for their own business school. The students were assessed for rigidity of cognitive orientation, and divided into open‐minded groups, and two other groups of more rigid orientation. Strategic plans were rated for originality and relevance. An open minded orientation affected the production of a strategic plan in a positive way. The productivity (quantity) of the more closed‐mind type of group was enhanced in the elaboration of a strategic plan through interventions introducing creativity. The quality of production was only marginally enhanced. We conclude that creativity‐enhancing techniques had a marginal direct effect on efforts to deal with ill‐defined problems such as a strategic plan. Additional indirect effects (by influencing rigid cognitive orientation) may be occurring.  相似文献   
8.
Cytochrome c (cyt c), a redox protein involved in diverse fundamental biological processes, is among the most traditional model proteins for analyzing biological electron transfer and protein dynamics both in solution and at membranes. Studying the role of electric fields in energy transduction mediated by cyt c relies upon appropriate reporter groups. Up to now these had to be introduced into cyt c by in vitro chemical modification. Here, we have overcome this restriction by incorporating the noncanonical amino acid p‐cyanophenylalanine (pCNF) into cyt c in vivo. UV and CD spectroscopy indicate preservation of the overall protein fold, stability, and heme coordination, whereas a small shift of the redox potential was observed by cyclic voltammetry. The C≡N stretching mode of the incorporated pCNF detected in the IR spectra reveals a surprising difference, which is related to the oxidation state of the heme iron, thus indicating high sensitivity to changes in the electrostatics of cyt c.  相似文献   
9.
A graphene/TiO2 nanocrystals hybrid has been successfully prepared by directly growing TiO2 nanocrystals on graphene oxide (GO) sheets. The direct growth of the nanocrystals on GO sheets was achieved by a two-step method, in which TiO2 was first coated on GO sheets by hydrolysis and crystallized into anatase nanocrystals by hydrothermal treatment in the second step. Slow hydrolysis induced by the use of EtOH/H2O mixed solvent and addition of H2SO4 facilitates the selective growth of TiO2 on GO and suppresses growth of free TiO2 in solution. The method offers easy access to the GO/TiO2 nanocrystals hybrid with a uniform coating and strong interactions between TiO2 and the underlying GO sheets. The strong coupling gives advanced hybrid materials with various applications including photocatalysis. The prepared graphene/TiO2 nanocrystals hybrid has superior photocatalytic activity to other TiO2 materials in the degradation of rhodamine B, showing an impressive three-fold photocatalytic enhancement over P25. It is expected that the hybrid material could also be promising for various other applications including lithium ion batteries, where strong electrical coupling to TiO2 nanoparticles is essential.  相似文献   
10.
Liquid water transport in the diffusion porous layers of polymer electrolyte membrane fuel cells (PEMFC) is analyzed as a process of quasi-static invasion from multiple interfacial injection sources. From pore network simulations based on a new version of the invasion percolation algorithm it is shown that a porous layer acts as a two-phase filter: the number of breakthrough points is significantly lower that the number of injection points owing to the merging of liquid paths within the porous layer. The number of breakthrough points at the gas diffusion layer/gas channel interface obtained with this model is consistent with the available experimental observations.  相似文献   
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