Plant fibers

植物纤维
  • 文章类型: Journal Article
    骨折钢板通常由钛合金或不锈钢制成,比骨头硬得多。然而,过于坚硬的钢板可以限制骨折处的轴向碎片间运动,导致延迟的骨痂形成和愈合。以及导致骨板下的骨“应力屏蔽”导致骨萎缩,骨吸收,和板松动。因此,以前已经做出了许多努力来开发使用合成纤维具有定制材料特性的非金属骨折板(例如,芳纶,碳,玻璃)在聚合物树脂中。即便如此,植物纤维(例如,亚麻,罗塞尔,剑麻)提供比合成纤维更多的优势,例如可用性,生物降解性,加工过程中毒性较小,更低的财务成本,和可回收性。因此,人们对单独使用植物纤维有了新的兴趣,或与合成纤维结合,增强聚合物的各种应用。因此,这是对由植物纤维单独增强或使用合成纤维补充的复合材料制成的创新骨折板的材料性能和工程性能的第一篇综述文章。本文介绍了材料级纤维性能(例如,弹性模量,极限强度),材料级板材属性(例如,疲劳强度,冲击韧性),和骨板工程性能(例如,总刚度,板应力),除了讨论一般发现,学习质量,未来的工作。这篇文章可以帮助工程师和外科医生设计,制造,分析,并利用新型骨折钢板。
    Bone fracture plates are usually made from titanium alloy or stainless steel, which are much stiffer than bone. However, overly stiff plates can restrict axial interfragmentary motion at the fracture leading to delayed callus formation and healing, as well as causing bone \"stress shielding\" under the plate leading to bone atrophy, bone resorption, and plate loosening. Consequently, there have been many prior efforts to develop nonmetallic bone fracture plates with customized material properties using synthetic fibers (e.g., aramid, carbon, glass) in polymer resin. Even so, plant fibers (e.g., flax, roselle, sisal) offer additional advantages over synthetic fibers, such as availability, biodegradability, less toxicity during processing, lower financial cost, and recyclability. As such, there is an emerging interest in using plant fibers alone, or combined with synthetic fibers, to reinforce polymers for various applications. Thus, this is the first review article on the material properties and engineering performance of innovative bone fracture plates made from composite materials reinforced by plant fibers alone or supplemented using synthetic fibers. This article presents material-level fiber properties (e.g., elastic modulus, ultimate strength), material-level plate properties (e.g., fatigue strength, impact toughness), and bone-plate engineering performance (e.g., overall stiffness, plate stress), as well as discussing general findings, study quality, and future work. This article may help engineers and surgeons to design, fabricate, analyze, and utilize novel bone fracture plates.
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  • 文章类型: Journal Article
    高糖消耗与心血管疾病和糖尿病有关。目前的糖替代品可能会引起味觉和胃肠道症状。ENSO16是16种不同的糖替代品和植物纤维的组合,已被设计为糖替代品。尚未研究对血浆葡萄糖代谢以及对胃肠道耐受性的影响。17名健康参与者参加了这项随机研究,双盲审判.参与者接受30g葡萄糖或30gENSO16的单次口服剂量,并在7天的冲洗期后交叉进行替代治疗。研究终点是对血浆葡萄糖的影响,胰岛素,C肽浓度和胃肠道疾病。使用有关胃肠道症状的问卷进行个人主观评分。与ENSO16相比,施用葡萄糖后平均基线调整的血浆葡萄糖AUC0-180分钟显著更大(n=15,p=0.0128,配对t检验)。口服葡萄糖或ENSO16后,相对于基线的最大血浆葡萄糖升高分别为117mg*dl-1和20mg*dl-1。与ENSO16摄入相比,在葡萄糖后,胰岛素和C肽AUC0-180分钟显著更大(p<0.01,Wilcoxon秩和检验)。血浆葡萄糖的平均最大浓度,与ENSO16摄入量相比,摄入葡萄糖后的胰岛素和C肽分别为摄入葡萄糖后的1.5、4.6和2.7倍,分别。不良反应大多轻微,治疗之间没有差异。结论。ENSO16对血浆葡萄糖代谢只有很小的影响。这在饮食环境中可能是有意义的,并且可能有助于减少卡路里的摄入。步道注册NCT05457400。首次注册:2022年7月14日。https://clinicaltrials.gov/study/NCT05457400.
    High sugar consumption is associated with cardiovascular diseases and diabetes. Current sugar substitutes may cause taste sensations and gastrointestinal symptoms. ENSO 16 is a combination of 16 different sugar substitutes and plant fibers and has been designed as a sugar alternative. The impact on plasma glucose metabolism as well as on gastrointestinal tolerance has not been investigated yet. 17 healthy participants were enrolled in this randomized, double-blind trial. Participants received a single oral dose of 30 g glucose or 30 g ENSO 16 and crossed over to the alternate treatment after a 7 day wash out period. The study endpoint was the effect on plasma glucose, insulin, C-peptide concentrations and gastrointestinal disorders. A questionnaire regarding gastrointestinal symptoms was used for individual subjective scoring. The mean baseline adjusted plasma glucose AUC0-180 min was significantly greater after glucose administration compared to ENSO 16 (n = 15, p = 0.0128, paired t-test). Maximum plasma glucose elevation over baseline was 117 mg*dl-1 and 20 mg*dl-1 after oral glucose or ENSO 16, respectively. Insulin and C-peptide AUC0-180 min were significantly greater after glucose compared to ENSO 16 intake (p < 0.01, Wilcoxon rank sum test). The mean maximal concentrations of plasma glucose, insulin and C-peptide after glucose intake were 1.5, 4.6 and 2.7-fold greater after glucose intake compared to ENSO 16 intake, respectively. Adverse reactions were mostly mild and not different between treatments. Conclusion. ENSO 16 has only a small impact on plasma glucose metabolism. This may be of interest in a dietary context and may help to reduce calory intake.Trail registration NCT05457400. First registration: 14/07/2022. https://clinicaltrials.gov/study/NCT05457400 .
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  • 文章类型: Journal Article
    结论:在几种苔藓种配子体的外茎皮层中发育出具有特定结构和聚合物组成的增厚细胞壁的纤维样细胞,其中包括(1→4)-β-半乳聚糖。早期的陆地植物进化出几种特殊的细胞类型和组织,这些细胞类型和组织在其水生祖先中不存在。其中,导水元素和生殖器官受到了大多数研究关注。尽管专门用于实现机械功能的组织的进化在陆地植物中分布广泛,但研究却很少。对于遵循同质轨迹的维管植物,主要讨论了机械组织的进化出现,主要是从具有基于木聚糖和木质素的细胞壁的皮下立体或硬化纤维的蕨类植物开始的。然而,苔藓植物也面临着机械挑战,缺乏木质化的细胞壁。为了表征苔藓植物谱系中的机械组织,沿着多元的轨迹,我们使用了六种野生苔藓(Polytrichumjuniperinum,Dicranumsp.,罗氏,Eurhynchiadelphussp.,爬虫,和Hylocombiumsplendens)并分析了其细胞壁的结构和组成。在他们所有人中,叶状配子体世代的外茎皮层具有纤维样细胞,细胞壁增厚但未木质化。这样的细胞具有带有尖头的纺锤形形状。这些纤维样细胞中额外的厚细胞壁层由具有不同纤维素微原纤取向的结构证据的亚层组成,并且具有包括(1→4)-β-半乳聚糖的特定聚合物组成。因此,在维管植物类群中提供机械支持的细胞的基本细胞特征(细长的细胞形状,位于主要器官的外围,增厚的细胞壁及其独特的组成和结构)也存在于苔藓中。
    CONCLUSIONS: Fiber-like cells with thickened cell walls of specific structure and polymer composition that includes (1 → 4)-β-galactans develop in the outer stem cortex of several moss species gametophytes. The early land plants evolved several specialized cell types and tissues that did not exist in their aquatic ancestors. Of these, water-conducting elements and reproductive organs have received most of the research attention. The evolution of tissues specialized to fulfill a mechanical function is by far less studied despite their wide distribution in land plants. For vascular plants following a homoiohydric trajectory, the evolutionary emergence of mechanical tissues is mainly discussed starting with the fern-like plants with their hypodermal sterome or sclerified fibers that have xylan and lignin-based cell walls. However, mechanical challenges were also faced by bryophytes, which lack lignified cell-walls. To characterize mechanical tissues in the bryophyte lineage, following a poikilohydric trajectory, we used six wild moss species (Polytrichum juniperinum, Dicranum sp., Rhodobryum roseum, Eurhynchiadelphus sp., Climacium dendroides, and Hylocomium splendens) and analyzed the structure and composition of their cell walls. In all of them, the outer stem cortex of the leafy gametophytic generation had fiber-like cells with a thickened but non-lignified cell wall. Such cells have a spindle-like shape with pointed tips. The additional thick cell wall layer in those fiber-like cells is composed of sublayers with structural evidence for different cellulose microfibril orientation, and with specific polymer composition that includes (1 → 4)-β-galactans. Thus, the basic cellular characters of the cells that provide mechanical support in vascular plant taxa (elongated cell shape, location at the periphery of a primary organ, the thickened cell wall and its peculiar composition and structure) also exist in mosses.
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  • 文章类型: Journal Article
    许多植物纤维中存在的富含纤维素的三级细胞壁具有特定的组成,architecture,机器的形成,和功能。为了更好地了解其作用方式的潜在机制,并揭示来自不同植物物种的纤维的特殊性,有必要更深入地描述主要成分。除了压倒性的纤维素,鼠李糖半乳糖醛酸I(RG-I)被认为是三级细胞壁的关键聚合物;然而,它已被分离并在极少数植物物种中进行了生化表征。这里,我们将RG-I添加到通过核磁共振(NMR)分离和分析的菜豆茎的韧皮纤维列表中,动态光散射,和免疫标记,在组织内和作为分离的聚合物。此外,具有来自Malphigiales目的九种双子叶植物的三级细胞壁的纤维,Fabales,和Rosales用RG-I相关抗体标记以检查聚合物的存在并比较其主链和侧链的原位呈递。获得的结果证实RG-I是三级细胞壁的强制性聚合物。然而,来自各种植物来源的这种聚合物的结构存在差异,这些特性可能在分类上相关。
    The cellulose-enriched tertiary cell walls present in many plant fibers have specific composition, architecture, machinery of formation, and function. To better understand the mechanisms underlying their mode of action and to reveal the peculiarities of fibers from different plant species, it is necessary to more deeply characterize the major components. Next to overwhelming cellulose, rhamnogalacturonan I (RG-I) is considered to be the key polymer of the tertiary cell wall; however, it has been isolated and biochemically characterized in very few plant species. Here, we add RG-I to the list from the phloem fibers of the Phaseolus vulgaris stem that was isolated and analyzed by nuclear magnetic resonance (NMR), dynamic light scattering, and immunolabeling, both within tissue and as an isolated polymer. Additionally, fibers with tertiary cell walls from nine species of dicotyledonous plants from the orders Malphigiales, Fabales, and Rosales were labeled with RG-I-related antibodies to check the presence of the polymer and compare the in situ presentation of its backbone and side chains. The obtained results confirm that RG-I is an obligatory polymer of the tertiary cell wall. However, there are differences in the structure of this polymer from various plant sources, and these peculiarities may be taxonomically related.
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  • 文章类型: Journal Article
    由于重金属对人类的毒性,几十年来一直是人们关注的问题,环境,和其他生物。近年来,使用基于纤维植物的食物垃圾材料产生的廉价且大量可用的生物吸附剂来去除重金属已经引起了相当多的研究关注。这篇综述的目的是研究使用基于纤维植物的食物垃圾的适用性,它包含不同的成分,如果胶,半纤维素,纤维素,还有木质素,去除废水中的重金属。这一贡献证实了植物纤维基食品垃圾具有结合废水和水溶液中重金属的潜力。这些生物吸附剂的结合能力因来源而异,化学结构,金属类型,应用的改性技术,和用于改善功能的工艺条件。这篇综述最后讨论了论点和前景,以及未来的研究方向,支持以纤维植物为基础的食物垃圾的价值化,作为一种有效和有前途的水净化策略。
    Mobilization of heavy metals in the environment has been a matter of concern for several decades due to their toxicity for humans, environments, and other living organisms. In recent years, use of inexpensive and abundantly available biosorbents generated from fibrous plant-based food-waste materials to remove heavy metals has garnered considerable research attention. The aim of this review is to investigate the applicability of using fibrous plant-based food waste, which comprises different components such as pectin, hemicellulose, cellulose, and lignin, to remove heavy metals from wastewater. This contribution confirms that plant-fiber-based food waste has the potential to bind heavy metals from wastewater and aqueous solutions. The binding capacities of these biosorbents vary depending on the source, chemical structure, type of metal, modification technology applied, and process conditions used to improve functionalities. This review concludes with a discussion of arguments and prospects, as well as future research directions, to support valorization of fibrous plant-based food waste as an efficient and promising strategy for water purification.
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  • 文章类型: Journal Article
    The production of bio-based composites with enhanced characteristics constitutes a strategic action to minimize the use of fossil fuel resources. The mechanical performances of these materials are related to the specific properties of their components, as well as to the quality of the interface between the matrix and the fibers. In a previous research study, it was shown that the polarity of the matrix played a key role in the mechanisms of fiber breakage during processing, as well as on the final properties of the composite. However, some key questions remained unanswered, and new investigations were necessary to improve the knowledge of the interactions between a lignocellulosic material and a polar matrix. In this work, for the first time, atomic force microscopy based on force spectroscopy measurements was carried out using functionalized tips to characterize the intermolecular interactions at the single molecule level, taking place between poly(butylene succinate) and four different plant fibers. The efficiency of the tip functionalization was checked out by scanning electron microscopy and energy-dispersive X-ray spectroscopy, whereas the fibers chemistry was characterized by Fourier-transform infrared spectroscopy. Larger interactions at the nanoscale level were found between the matrix and hypolignified fibers compared to lignified ones, as in control experiments on single lignocellulosic polymer films. These results could significantly aid in the design of the most appropriate composite composition depending on its final use.
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  • 文章类型: Journal Article
    医疗保健相关感染(HAI),或医院感染,是发达国家和发展中国家的全球健康和经济问题,特别是对于重症监护病房(ICU)和手术场所医院区域的免疫功能低下的患者。HAIs中的复发性病原体优于抗生素抗性细菌,如耐甲氧西林金黄色葡萄球菌(MRSA)和铜绿假单胞菌。出于这个原因,天然抗菌机制是HAI治疗的可行替代方案。天然纤维可以抑制细菌生长,这在这些应用中可以被认为是一个很大的优势。此外,据报道,这些纤维具有生物相容性和可生物降解性,生物医学材料的基本特征,以避免由于感染和显着的免疫反应引起的并发症。因此,组织工程,医用纺织品,骨科,和牙科植入物,以及化妆品,是目前正在扩大植物纤维使用的领域。在这次审查中,我们将讨论具有抗菌性能的天然纤维的来源,抗菌机制,以及它们的生物医学应用。
    Healthcare-associated infections (HAI), or nosocomial infections, are a global health and economic problem in developed and developing countries, particularly for immunocompromised patients in their intensive care units (ICUs) and surgical site hospital areas. Recurrent pathogens in HAIs prevail over antibiotic-resistant bacteria, such as methicillin-resistant Staphylococcus aureus (MRSA) and Pseudomonas aeruginosa. For this reason, natural antibacterial mechanisms are a viable alternative for HAI treatment. Natural fibers can inhibit bacterial growth, which can be considered a great advantage in these applications. Moreover, these fibers have been reported to be biocompatible and biodegradable, essential features for biomedical materials to avoid complications due to infections and significant immune responses. Consequently, tissue engineering, medical textiles, orthopedics, and dental implants, as well as cosmetics, are fields currently expanding the use of plant fibers. In this review, we will discuss the source of natural fibers with antimicrobial properties, antimicrobial mechanisms, and their biomedical applications.
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  • 文章类型: Journal Article
    该评论以许多植物的纤维沉积的令人印象深刻的富含纤维素的细胞壁为例,总结了材料设计上的植物生命。这种特定的细胞壁类型被称为三级细胞壁,因为它在次生细胞壁之后沉积,并且在形成和功能机制上非常不同。三级细胞壁性能的基本原理包括:1)原始组成(两个主要参与者-纤维素微纤维和形成特定超分子结构的鼠李糖半乳糖醛酸I的版本);2)所有纤维素微纤维的轴向取向的原始细胞壁设计,它们之间明显的横向相互作用以及诱捕的鼠李糖半乳糖醛酸I的存在;3)在纤维成熟过程中,由于鼠李糖半乳糖醛酸I在muro中的修饰,细胞壁超分子组织的动态变化;4)追踪细胞壁状态的内置传感器;5)将三级细胞壁掺入具有较高组织水平的系统中。
    The review summarizes the plant lifehacks on material design on the example of the impressive cellulose-enriched cell wall deposited by fibers of many plants. This specific cell wall type is called tertiary since it is deposited after the secondary cell wall and is very distinct in the machinery of formation and function. The basic principles of tertiary cell wall performance include: 1) original composition (two major players - cellulose microfibrils and the version of rhamnogalacturonan I that forms specific supramolecular structures); 2) original cell wall design with axial orientation of all cellulose microfibrils, pronounced lateral interactions between them and the presence of the entrapped rhamnogalacturonan I; 3) dynamic changes in cell wall supramolecular organization due to rhamnogalacturonan I modifications in muro in the course of fiber maturation; 4) the built-in sensors that trace the cell wall state; 5) incorporation of tertiary cell wall into the system with higher level of organization.
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  • 文章类型: Journal Article
    可持续发展涉及使用替代可持续材料,以维持自然资源的过度消耗。植物纤维,作为“绿色”材料,正在逐步获得建筑领域各种研究人员的关注,因为它们在复合材料中的潜在用途是迈向可持续发展。本研究旨在对植物纤维及其作为建筑和建筑材料的应用背景进行科学综述。总结了过去二十年的研究。通过使用文献计量数据之间的联系和映射来定量评估研究进展,这些文献计量数据是为使用Scopus分析植物纤维而编制的。还使用了数据细化技术。植物纤维可能用于增强复合材料的机械性能。从文献中可以看出,与用于土木工程应用的人造/钢纤维增强的复合材料相比,植物纤维增强的复合材料具有可比的性能。如建筑材料,桥墩,运河衬里,土壤加固,人行道,声学处理,绝缘材料,等。然而,植物纤维的可生物降解性质仍然阻碍了它们作为结构材料的应用。为此,不同的表面和化学处理方法已在过去的研究中提出,以提高其耐久性。从收集的数据可以推测,植物纤维增强水泥基复合材料的抗压强度和抗弯强度增加了43%和67%,分别,关于参考复合材料。在文学中,碱处理已被报道为处理植物纤维的有效和经济的方法。建筑业过度消耗自然资源和化石燃料造成的环境退化,随着废弃植物纤维的燃烧,可以通过在水泥基复合材料中掺入所述纤维来减少垃圾填埋污染,最终,实现可持续发展。
    Sustainable development involves the usage of alternative sustainable materials in order to sustain the excessive depletion of natural resources. Plant fibers, as a \"green\" material, are progressively gaining the attention of various researchers in the field of construction for their potential use in composites for stepping towards sustainable development. This study aims to provide a scientometric review of the summarized background of plant fibers and their applications as construction and building materials. Studies from the past two decades are summarized. Quantitative assessment of research progress is made by using connections and maps between bibliometric data that are compiled for the analysis of plant fibers using Scopus. Data refinement techniques are also used. Plant fibers are potentially used to enhance the mechanical properties of a composite. It is revealed from the literature that plant-fiber-reinforced composites have comparable properties in comparison to composites reinforced with artificial/steel fibers for civil engineering applications, such as construction materials, bridge piers, canal linings, soil reinforcement, pavements, acoustic treatment, insulation materials, etc. However, the biodegradable nature of plant fibers is still a hindrance to their application as a structural material. For this purpose, different surface and chemical treatment methods have been proposed in past studies to improve their durability. It can be surmised from the gathered data that the compressive and flexural strengths of plant-fiber-reinforced cementitious composites are increased by up to 43% and 67%, respectively, with respect to a reference composite. In the literature, alkaline treatment has been reported as an effective and economical method for treating plant fibers. Environmental degradation due to excessive consumption of natural resources and fossil fuels for the construction industry, along with the burning of waste plant fibers, can be reduced by incorporating said fibers in cementitious composites to reduce landfill pollution and, ultimately, achieve sustainable development.
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  • 文章类型: Journal Article
    这项工作受到当前欧洲旨在减少塑料废物的政策的启发。包装行业尤其如此。该工作中开发的生物复合材料属于环保塑料组,可以减少未来不断增加的环境费成本。三种类型的短纤维(亚麻,选择长度为1mm的大麻和木材)作为填料(PHBV中质量含量为30%)。将生物复合材料挤出,然后通过具有相同技术参数的注塑工艺进行加工。测试以这种方式获得的样品的机械性能和模塑件的质量。与纯PHBV相比,含有大麻和亚麻纤维的生物复合材料的某些机械性能以及成型件的质量得到了显着改善。仅在木材-PHBV生物复合材料的情况下,与本研究中使用的其他填料的生物复合材料相比,获得的性能没有显着改善。天然纤维的使用,特别是大麻纤维作为PHBV基质中的填料,在大多数情况下,对改善成型件的机械性能和质量具有积极作用。此外,应该记住,获得的生物复合材料是天然来源的,是完全可生物降解的,这是有趣和理想的特性,是现代生物材料生产和商业化的当前趋势的一部分。
    This work is inspired by the current European policies that aim to reduce plastic waste. This is especially true of the packaging industry. The biocomposites developed in the work belong to the group of environmentally friendly plastics that can reduce the increasing costs of environmental fees in the future. Three types of short fibers (flax, hemp and wood) with a length of 1 mm each were selected as fillers (30% mass content in PHBV). The biocomposites were extruded and then processed by the injection molding process with the same technical parameters. The samples obtained in this way were tested for mechanical properties and quality of the molded pieces. A significant improvement of some mechanical properties of biocomposites containing hemp and flax fibers and quality of molded pieces was obtained in comparison with pure PHBV. Only in the case of wood-PHBV biocomposites was no significant improvement of properties obtained compared to biocomposites with other fillers used in this research. The use of natural fibers, in particular hemp fibers as a filler in the PHBV matrix, in most cases has a positive effect on improving the mechanical properties and quality of molded pieces. In addition, it should be remembered that the obtained biocomposites are of natural origin and are fully biodegradable, which are interesting and desirable properties that are a part of the current trend regarding the production and commercialization of modern biomaterials.
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