Imogolite occurs as tiny bumps less than 0.05 µm in diameter and about 0.3 µm long on amorphous thin layers on the surface of weathered plagioclase. The bumps grow outward from the surface to form projections, which then develop into a fibrous imogolite. The fibers branch out and grow into widespread networks or thin films which finally cover the entire surface of the plagioclase grain. The fibers are about 0.05 µm in diameter as seen by transmission electron microscopy.

Woolly erionite from the Reese River deposit, Nevada, is identical in appearance to that at the type locality, near Durkee, Oregon. Both of these erionites differ in appearance from all other erionite reported in the past 20 years from diverse rocks throughout the world which are described as prismatic or acicular in habit. The non-woolly erionites are especially common as microscopic crystals in diagenetically altered vitroclastic lacustrine deposits of Cenozoic age. The Reese River woolly erionite fills joints in gray to brownish-gray lacustrine mudstone of probably Pliocene age, in a zone about 1 m thick beneath a conspicuous gray vitric tuff. Compact masses of long, curly, woolly erionite fibers are in the plane of the joint and locally are associated with opal. Indices of refraction are ω = 1.468 and ε = 1.472; hexagonal unit-cell parameters are a = 13.186(2) Å, c = 15.055(1) Å, and V = 2267.1(0.9) Å3. A chemical analysis of woolly erionite yields a unit-cell composition of: Na1.01K2.84Mg0.3Ca1.69Al8.18Si27.84O72·28.51H2O.

Imogolite was synthesized at 25°C by aging partially neutralized solutions containing monomeric silicic acid and polymeric hydroxy-aluminum ions for 7 years. Solutions having an initial Si/Al molar ratio of about 0.5 and pHs of 4.0–4.5 produced the largest yields of imogolite, followed by those having an initial Si/Al ratio of about 1, although imogolite was not the principal product. Electron microscopic examination showed a small amount of imogolite fibers embedded in a noncrystalline gel-like substance. Traces of imogolite were detected in solutions having an initial Si/Al ratio of about 2, but no imogolite was found by electron microscopy in products from solutions having an initial Si/Al ratio of about 4. Only gibbsite formed from solutions having initial Si/Al ratios of <0.27. The diameter of the tubular structural unit of the imogolite produced in these experiments was 23 ± 2Å, close to that of natural imogolite.

The occurrence of palygorskite in some Tertiary sediments in eastern Saudi Arabia was studied. Mineralogical and chemical analyses were made of samples from two sections several meters thick from the Umm er Radhuma and Dammam Formations of Paleocene and Eocene periods, respectively. Layers of shales were observed within the sections of the dolomitic-calcitic limestone of the Umm er Radhuma Formation and of the dolomitic limestone of the Dammam Formation. After treatment for carbonate removal the shales consisted of more than 95% clay-size particles, most of which were <0.2-μm in size. Palygorskite was the main constituent of some of the shales, with minor amounts of gypsum, soluble salts, and carbonates. The association of gypsum and other salts with palygorskite in the shale suggests that palygorskite formed in closed-basin environments. The presence of palygorskite and the absence of other minerals in the clay fraction of the limestones also suggests that the palygorskite formed under marine conditions.

We investigated the influence of maternal yellow-pea fiber supplementation in obese pregnancies on offspring metabolic health in adulthood. Sixty newly-weaned female Sprague-Dawley rats were randomized to either a low-calorie control diet (CON) or high calorie obesogenic diet (HC) for 6-weeks. Obese animals were then fed either the HC diet alone or the HC diet supplemented with yellow-pea fiber (HC + FBR) for an additional 4-weeks prior to breeding and throughout gestation and lactation. On postnatal day (PND) 21, 1 male and 1 female offspring from each dam were weaned onto the CON diet until adulthood (PND 120) for metabolic phenotyping. Adult male, but not female, HC offspring demonstrated increased body weight and feed intake vs CON offspring, however no protection was offered by maternal FBR supplementation. HC male and female adult offspring demonstrated increased serum glucose and insulin resistance (HOMA-IR) compared with CON offspring. Maternal FBR supplementation improved glycemic control in male, but not female offspring. Compared with CON offspring, male offspring from HC dams demonstrated marked dyslipidemia (higher serum cholesterol, increased number of TG-rich lipoproteins, and smaller LDL particles) which was largely normalized in offspring from HC + FBR mothers. Male offspring born to obese mothers (HC) had higher hepatic TG, which tended to be lowered (p = 0.07) by maternal FBR supplementation.

Supplementation of a maternal high calorie diet with yellow-pea fiber in prepregnancy and throughout gestation and lactation protects male offspring from metabolic dysfunction in the absence of any change in body weight status in adulthood.

Many persons with spinal cord injury (SCI) have one or more preventable chronic diseases related to excessive energetic intake and poor eating patterns. Appropriate nutrient consumption relative to need becomes a concern despite authoritative dietary recommendations from around the world. These recommendations were developed for the non-disabled population and do not account for the injury-induced changes in body composition, hypometabolic rate, hormonal dysregulation and nutrition status after SCI. Because evidence-based dietary reference intake values for SCI do not exist, ensuring appropriate consumption of macronutrient and micronutrients for their energy requirements becomes a challenge. In this compressive review, we briefly evaluate aspects of energy balance and appetite control relative to SCI. We report on the evidence regarding energy expenditure, nutrient intake and their relationship after SCI. We compare these data with several established nutritional guidelines from American Heart Association, Australian Dietary Guidelines, Dietary Guidelines for Americans, Institute of Medicine Dietary Reference Intake, Public Health England Government Dietary Recommendations, WHO Healthy Diet and the Paralyzed Veterans of America (PVA) Clinical Practice Guidelines. We also provide practical assessment and nutritional recommendations to facilitate a healthy dietary pattern after SCI. Because of a lack of strong SCI research, there are currently limited dietary recommendations outside of the PVA guidelines that capture the unique nutrient needs after SCI. Future multicentre clinical trials are needed to develop comprehensive, evidence-based dietary reference values specific for persons with SCI across the care continuum that rely on accurate, individual assessment of energy need.

Growing zinc oxide (ZnO) nanowires (NWs) on yarns promotes smart sensing and creates opportunities for new applications. ZnO NWs sensing performance is influenced by its dimensions, which can be tailored by controlling the growth parameters. In this study, we investigated the effect of the growth parameters (time, temperature, and precursor concentration ratio) on the NWs’ morphology, dimensions, and piezoelectric performance. Our results showed that ZnO NWs produced with 6 and 9 h had long nanowires; however, they mainly got tangled with the nanowires on the adjacent fibers and peeled-off the fiber surface. Growth at a 1:1 precursor concentration ratio for 9 h produced the same nanowires’ length (~3 μm) as growth at a 3:1 precursor concentration ratio for 3 h. Among all of the studied growth conditions, ZnO NWs produced with a 3:1 precursor concentration ratio at 90 °C for 3 h showed uniform dimensions and stable electrical charge output.

Cellprene™ is a recently developed polymeric blend based on poly(lactide-co-glycolide) (PLGA)/polyisoprene (PI) with good biological performance for biomedical applications. However, its potential as fiber scaffold in tissue engineering is still unknown, and the influence of processing parameters is yet to be understood. In this study, several compositions based on PLGA/PI blend mixed with hydroxyapatite (HAp) and polyethylene glycol (PEG) were prepared by solvent casting. Then, the membranes were used to produce micro/nanofibers by centrifugal spinning (CS) and electrospinning (ES). The viscosity's effect was studied to find an ideal viscosity value to produce homogeneous micro/nanofibers. The in vitro bioactivity test was also performed. Rheological results showed that the best viscosity range was (0.105 Pa s > η > 0.138 Pa s) for CS; larger fibers of ES were produced with lower viscosities. The sample with the lowest HAp concentration exhibited thinner and more homogeneous non-beaded fibers and proved its bioactivity response.

This paper presents the characterization of laterite-cement-based matrix composites, reinforced with chemically modified bamboo fibers. Fiber extraction and chemical modification were first explored by soaking slabs of bamboos in NaOH solution (5 wt.% of NaOH in distilled water) for 14 days. Fiber characterization, as well as the flexural and compressive strength of reinforced composites, were carried out with MTS universal mechanical testing machine. Comparative results on the compressive and flexural strength were obtained at 80 wt.% laterite (L) to 20 wt.% cement (C) with fiber ratios from 5-25 wt%. The compressive strength of the composites varied from 7.2 MPa (at 5 wt.% bamboo fiber) to 17.67 MPa (at 25 wt% fiber blocks). The hardness of the composites was found to improve from 66.67-75.0 HD with bamboo fibers. Results were then discussed for possible structural applications such as enhancing low-cost building blocks for rural communities in Ghana.

The effect of the combined chemical treatment of sisal fibres through the subsequent processes of mercerisation (alkali-treatment), then silane treatment and eventually acid hydrolysis, on sisal fibre were investigated. The effect of the treated fibres on the tensile strength and stiffness, flexural strength and stiffness, compression strength and shear strength of their composites with epoxy resin were also studied. Scanning electron microscopy studies of the surfaces of the treated and untreated fibres showed that the chemical treatment processes enhanced the removal of surface extractives and therefore increased the roughness of the surfaces of the fibres in the range of 20 % - 70 %. This avails an increased reinforcement surface area for interlocking with matrix and is, therefore, expected to enhance adhesion of the two. The treated fibre reinforced composites were observed to have higher values of tensile strength and stiffness, flexural strength and stiffness, compression strength and shear strength than the un-treated fibre reinforced composites. These higher values were attributed to better interfacial bonding due to better mechanical interlocking between the treated fibres and epoxy resin arising from the increased roughness of the treated fibres.

Stabilized earth is a very ancient material that has been used in many countries as a low cost, environment friendly construction material. However, its durability under humid environments is low. Stabilization using cement, lime and natural fibres could enhance its durability and lowers the risk of cracking. This paper presents an experimental investigation into the performance of stabilised local soil by either, cement mixed with a proportion of granulated blast furnace slag (GBFS) /or straw naturel fibres. Unconfined compressive strength (UCS), shrinkage, wetting and drying, capillary absorption and thermal conductivity tests were performed on both untreated soil samples and stabilised soil samples. The results show that stabilising the soil with cement and GBFS increased both compressive strength, durability, thermal conductivity and decreased the capillary absorption and the shrinkage. The addition of natural wheat fibres increased the capillary absorption but leads to a decrease in the thermal conductivity and to a further reduction in the shrinkage and hence a better insulating less prone to cracking material.

This study aims to create controlled fine space by electrospinning, and to develop the electrode materials for high-performance energy devices. With the popularization of mobile devices, household appliances, hybrid vehicles, electric vehicles, and the like, the use of power storage devices is expanding, and further performance improvements are required. In this study, a novel electrode material was developed by compositing Si with carbon nanofibers derived from polyacrylonitrile (PAN) by electrospinning and heat treatment. The texture and structure of the nanofibers were observed and analyzed by scanning electron microscopy (SEM), energy dispersive X-ray spectrometry (EDX) and transmission electron microscopy (TEM) combined with image processing. Nano spaces were created in the CNFs and Si particles were able to be contained in the CNFs. In the second and subsequent cycles of the charge/discharge experiments of lithium ion battery (LIB) electrode made from the materials, the capacity was more than twice the theoretical capacity using graphite, and good cycle performance was obtained.

The dynamic mechanical force transmitted through microenvironments during tissue formation and regeneration continuously impacts the mechanics of cells and thereby regulates gene and protein expression. The mechanical properties are altered during the process of stem cells differentiating into different lineages. At different stages of differentiation, stem cells display different mechanical properties in response to surrounding microenvironments, which depend on the subcellular structures, especially the cytoskeleton and nucleus. The mechanical properties of the cell nucleus affect protein folding and transport as well as the condensation of chromatin, through which the cell fate is regulated. These findings raise the question as to how cell mechanics change during differentiation. In this study, the mechanical properties of human bone marrow mesenchymal stem cells (hBMSCs) were determined during adipogenic and osteogenic differentiation by atomic force microscopy (AFM). The cytoskeletal structure and the modification of histone were investigated using laser confocal microscope and flow cytometry. The mechanical properties of cell nuclei at different stages of cell differentiation were compared. The stiffness of nuclei increased with time as osteogenesis was induced in hBMSCs. The H3K27me3 level increased during osteogenesis and adipogenesis according to flow cytometry analysis. Our results show conclusively that AFM is a facile and effective method to monitor stem cell differentiation. The measurement of cell mechanical properties by AFM improves our understanding on the connection between mechanics and stem cell fate.

Carbon nanomaterials are consistently providing new excitement over their properties and potential applications, but many of these material have yet to fully live up to their expectations commercially. The barrier to adoption often exists as a result of complex processing, fragility of the as-produced material, or difficulty scaling beyond laboratory quantities. This work provides a new approach for utilizing fibrous carbon nanomaterials to advance the technology toward new applications and industrial utility. This is accomplished by creating tailored device architectures through in-situ integration of activated carbon powder using carbon nanofiber deposition. The resulting hybrid materials and components can serve in diverse applications, with each instance able to be fine-tuned through a combination of processing parameters. The applications of such materials are anticipated to directly serve current carbon-based technology in filtration, energy storage and delivery, and thermal management, but the concepts are not limited to current carbon applications.

Supercapacitors have the potential to complement or replace batteries in many current and emerging applications. As inexpensive and environmentally benign capacitive materials, manganese oxides are promising electrode materials. Nanostructured oxides have high energy storage capacities owing to their increased surface-area-to-volume ratios as compared to bulk materials. By electrospinning precursor-containing polymer fibers and subsequently calcining, nanostructured MnOx fibers can be prepared with relative ease. Controlling calcination pressure and time provides a route for variable capacitance via modifying surface roughness and oxide phase. At moderate pressures and short calcination times, mixed-phase Mn2O3/Mn3O4 fibers with high surface roughness exhibit enhanced electrochemical specific capacitance.

Silk and carbon nanomaterials, such as graphene oxide, graphene, and carbon nanotubes, have complementary mechanical properties that feature superior toughness and strength, respectively. Different strategies have been devoted to developing silk/carbon nanocomposites, but challenges remain to fully integrate the mechanical advantages of these two components into one synergistic material system. In this article, we provide a critical summary of structure–mechanics relationships in silk/carbon nanocomposites and highlight the impact of the interaction between silk and carbon nanomaterials on mechanical properties of the hybrid materials. We describe the challenges involved and directions for future designs of silk/carbon nanocomposites.