Secondary Fiber Research Articles

Relationship between nucleic acid structures and sequences on the expression of terminal differentiation (i.e., denucleation): alternative cell death pathway

Terminal differentiation (i.e., denucleation) is a type of cell death, similar to apoptosis and necrosis, and is considered an alternative cell death pathway. Denucleating secondary crystalline lens fiber cells, keratinocytes of the epidermis and erythrocytes use this cell death mechanism to maintain their normal cellular physiology. In all three cases, the overall process of organelle removal is somewhat understood morphologically and biochemically; however, the molecular biology is not fully known. Structural transitions of the canonical A‐RNA into alternative structures such as left‐handed Z‐RNA, and the formation of multistranded DNA's (e.g., quadruplex DNA) are important in cells. We are examining how structural polymorphisms play a role in regulating cell death in the three above mentioned tissues, namely, denucleation, and how it differs from apoptosis and necrosis. Immunohistochemistry was performed to study the distribution and specific amounts of single‐stranded (ss−) DNA, A‐RNA, Z‐RNA and quadruplex DNA during denucleation. Immunohistochemical staining of tissue sections were performed with anti‐ss‐DNA, anti‐A‐RNA, anti‐Z‐RNA and anti‐quadruplex DNA antibodies. We observed ss‐DNA, A‐RNA, Z‐RNA and quadruplex DNA immunoreactivity. Both negative, positive and isotype controls were used. ELISA data correlates well with our immunohistochemical results. Immunohistochemical staining of tissues for the demonstration and quantification of ss‐DNA, A‐RNA, Z‐RNA and G4‐quadruplex DNA, reveals different levels of decreasing and increasing immunoreactivity as dying cells progress thru denucleation. Immunohistochemistry shows different levels of gradually decreasing quadruplex DNA as cells progress thru denucleation, with precipitous declines in certain tissue zones at specific times [i.e., this correlates well with decrease in B‐DNA (conrtols)]. A‐RNA and mainly Z‐RNA content decreases during denucleation. A decline in the presence of quadruplex DNA also reveals how denucleation is eradicating different DNA structures. This gradual decline in quadruplex DNA represents chromatin fragmentation. A precipitous decline in quadruplex DNA occurs towards the end of denucleation, depending on tissue type. We believe that specific types of canonical (e.g. B‐DNA), alternative (e.g., Z‐DNA) and multistranded DNAs (e.g., triplex DNA and quadruplex DNA) regulate pro‐ and anti‐cell death factors (e.g., DNase IIβ, CDK1, and cyclins in lens fiber cells, respectively), which control programmed elimination of cellular organelles and DNA. Pro‐cell death factors allows the denucleated cells to remain viable for a certain period of time. Denucleating keratinocytes, secondary crystalline lens fibers and erythrocytes share some common initial characteristics with apoptosis and necrosis, however, the latter part of denucleation is completely different. Based on our research we believe that pro‐apoptotic proteins are involved in the early stages of denucleation, and then other mechanisms (e.g., anti‐apoptotic) take over the remaining processes of terminal differentiation. The gradual decrease in A‐RNA, Z‐RNA and quadruplex DNA during denucleation may play a role in regulating this alternative cell death pathway. Our results suggest that dissimilar nucleic acid structures cause nucleic acid fragmentation in denucleating cells, which differs from apoptosis and necrosis, in the sequence of events and the time course.Support or Funding InformationProject was supported by several NYIT ISRC and TriBeta Biology Honor Society grants.This abstract is from the Experimental Biology 2018 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.

Deletion of GLUT1 in mouse lens epithelium leads to cataract formation

The primary energy substrate of the lens is glucose and uptake of glucose from the aqueous humor is dependent on glucose transporters. GLUT1, the facilitated glucose transporter encoded by Slc2a1 is expressed in the epithelium of bovine, human and rat lenses. In the current study, we examined the expression of GLUT1 in the mouse lens and determined its role in maintaining lens transparency by studying effects of postnatal deletion of Slc2a1. In situ hybridization and immunofluorescence labeling were used to determine the expression and subcellular distribution of GLUT1 in the lens. Slc2a1 was knocked out of the lens epithelium by crossing transgenic mice expressing Cre recombinase under control of the GFAP promoter with Slc2a1loxP/loxP mice to generate Slc2a1loxP/loxP;GFAP-Cre+/0 (LensΔGlut1) mice. LensΔGlut1 mice developed visible lens opacities by around 3 months of age, which corresponded temporally with the total loss of detectable GLUT1 expression in the lens. Spectral domain optical coherence tomography (SD-OCT) imaging was used to monitor the formation of cataracts over time. SD-OCT imaging revealed that small nuclear cataracts were first apparent in the lenses of LensΔGlut1 mice beginning at about 2.7 months of age. Longitudinal SD-OCT imaging of LensΔGlut1 mice revealed disruption of mature secondary fiber cells after 3 months of age. Histological sections of eyes from LensΔGlut1 mice confirmed the disruption of the secondary fiber cells. The structural changes were most pronounced in fiber cells that had lost their organelles. In contrast, the histology of the lens epithelium in these mice appeared normal. Lactate and ATP were measured in lenses from LensΔGlut1 and control mice at 2 and 3 months of age. At 2 months of age, when GLUT1 was still detectable in the lens epithelium, albeit at low levels, the amount of lactate and ATP were not significantly different from controls. However, in lenses isolated from 3-month-old LensΔGlut1 mice, when GLUT1 was no longer detectable, levels of lactate and ATP were 50% lower than controls. Our findings demonstrate that in vivo, the transparency of mature lens fiber cells was dependent on glycolysis for ATP and the loss of GLUT1 transporters led to cataract formation. In contrast, lens epithelium and cortical fiber cells have mitochondria and could utilize other substrates to support their anabolic and catabolic needs.

Thermo-catalytic reforming of co-form® rejects (waste cleansing wipes)

Co-form® products are typically used for personal hygiene care (cleansing wipes), household cleaning (pads and mops) and absorbent applications. Co-form® is a thermo-bonded multilayer nonwoven composite and Kimberly-Clark patented its process in 2008. Co-form® rejects are composed of 30% plastic polypropylene and 70% wood pulp fibre. It is difficult to recycle and to-date no research articles explore pyrolytic valorisation for its energy recovery. This paper investigated pyrolytic valorisation of co-form® rejects into energy vectors. Pelletised co-form® rejects obtained from a secondary fibre paper mill were processed using a laboratory scale 2 kg/h Thermo-Catalytic Reforming (TCR®) reactor. The TCR® process combines intermediate pyrolysis, using an auger reactor to heat the material under moderate temperatures (350–450 °C) and moderate solid residence times (minutes) in the complete absence of Oxygen, with post catalytic reforming in a fixed bed reactor at 700 °C. Pelletised co-form® rejects were successfully converted into 12 wt% bio-oil, 9 wt% aqueous phase liquid, 8 wt% char and 71 wt% syngas products. The bio-oil higher heating value was found to be 39.36 MJ/kg, comparable to biodiesel. Naphthalene was found to be the most abundant aromatic compound within the oil, with a relative abundance of 15.22% measured by GC–MS. Oleic acid methyl ester (15.86%) was the most abundant long chain hydrocarbon detected. The higher heating value of produced gas was 11.02 MJ Nm3 and char 30.79 MJ/kg. TCR® conversion of co-form® rejects proved to be a feasible route for the valorisation of this waste stream into sustainable energy vectors. In previous works, gasification processes could not successfully convert organic waste streams with a high plastic content, without implications attributed to agglomeration and melting of plastics. The TCR® process overcome these issues with no evidence of agglomeration or melting of plastics present within the reactor. The success was believed to be through applying moderate heating rates (°C/min) and temperatures (max 700 °C), as well as the mechanical effect of continuous mixing of material within the reactor via the internal auger screw. Overall, TCR® is a promising future route for the valorisation of co-form® rejects to produce energy vectors.

Development of distinct cell wall layers both in primary and secondary phloem fibers of hemp (Cannabis sativa L.)

Formation of thickened cell wall allows plant fibers to obtain the strength necessary to the realization of their function as mechanical tissue. It is due to such cell wall that fibers of textile crops, like flax, hemp, and ramie, acquire characteristics that make possible to use these fibers in textile and technical applications. In the hemp stem, primary and secondary phloem fibers originating from the different type of meristems are formed. Analysis of ultrastructure coupled with immunolabelling demonstrated distinct layers within thickened cell wall in the fiber of both types: the outer layer is built as typical secondary cell wall of xylan-type, while the major portion was identified as the layers of tertiary (gelatinous or G-layer) cell wall. A newly deposited layer of the tertiary cell wall (Gn) is transformed into mature G-layer by the post-synthetic modification. The general design of cell wall in primary and secondary phloem fibers is similar, but with xylan layer being considerably thicker in secondary fibers than in primary ones. The formation of the tertiary cell wall in primary and secondary hemp fibers was associated with the synthesis of pectin component – rhamnogalacturonan I together with β-(1,4)-d-galactan, which has been detected and characterized both in the buffer-extractable fraction and among the strongly retained within cell wall polysaccharides. Comparison of the obtained results with data on the flax fiber cell wall development permitted to find similarities, as well as some differences of G-fiber cell wall organization in different plant species.

Comparative study between Federer and Gomez method for number of replication in complete randomized design using simulation: study of Areca Palm (Areca catechu) as organic waste for producing handicraft paper

The part of Areca Palm (Areca catechu) that economical is the seed. It is commercially available in dried, cured and fresh forms, while the fibre is usually thrown away. Cellulose fibers from agricultural waste can be utilized as raw material for handicraft paper. Laboratory research showed that Areca palm fibre contained 70.2% of cellulose, 10.92% of water, and 6.02% of ash. This indicated that Areca palm fibre is very potential to be processed as handicraft paper. Handicraft paper is made of wastepaper or plants which cointain celluloce to produce rough-textured paper. In order to obtain preferred sensory quality of handicraft paper such as color, fiber appearance and texture as well as good physical quantity such as tensile strength, tear resistance and grammage, the addition of wastepaper to provide secondary fibre and sometimes adhesive are needed in making handicraft paper. Handicraft paper making was one alternative to treat the solid waste and to reduce the use of wood fiber as paper raw material. The aim of this study is to compare the two most famous method, i.e. Federer and Gomez Method, for calculate the number of replications. This study is preliminary research before do the research in order to get the best treatment to produce handicraft paper. The Gomez method calculates fewer replications than the Federer method. Based on data simulation the error generated using 3 replicates of 0.0876 while using 2 replicates of 0.1032.

Conductive hybrid polymer composites based on recycled carbon fibres and carbon nanofillers

The aim of this study was to investigate potential applications of milled secondary carbon fibres as a primary filler in conductive polymer composites. The examined composites were based on epoxy resin, milled secondary carbon fibres and selected carbon nanoadditive used as a secondary conductive filler. Three kinds of nanopowders were tested: multiwalled carbon nanotubes, graphene nanoplatelets and graphitized carbon black. In the first stage of the experiment, composites with different percentages of carbon fibres were examined in order to determine the electrical conductivity and percolation threshold. Subsequently, the most conductive composition (70% of carbon fibres, σ = 9.05 S cm−1) was modified by adding nanofillers. The addition of carbon nanotubes caused more than twofold increase in in-plane conductivity to 20.18 S cm−1. The composites with graphene nanoplatelets showed deterioration of properties due to strongly increased viscosity of a binder with graphene. Small loadings of graphitized carbon black had a minor positive impact on the electrical conductivity and mechanical properties of composites.

Association of Heritable Cognitive Ability and Psychopathology With White Matter Properties in Children and Adolescents

Many mental disorders emerge during adolescence, which may reflect a cost of the potential for brain plasticity offered during this period. Brain dysconnectivity has been proposed as a common factor across diagnostic categories. To investigate the hypothesis that brain dysconnectivity is a transdiagnostic phenotype in adolescence with increased susceptibility and symptoms of psychiatric disease. We investigated clinical symptoms as well as cognitive function in 6487 individuals aged 8 to 21 years from November 1, 2009, to November 30, 2011, in the Philadelphia Neurodevelopmental Cohort and analyzed diffusion magnetic resonance imaging brain scans for 748 of the participants. Independent component analysis was used to derive dimensional psychopathology scores, and genome-wide complex trait analysis was used to estimate its heritability. Multimodal fusion simultaneously modeled contributions of the diffusion magnetic resonance imaging metrics fractional anisotropy, mean diffusivity, radial diffusivity, L1 (the principal diffusion tensor imaging eigen value), mode of anisotropy, as well as dominant and secondary fiber orientations, and structural connectivity density, and their association with general psychopathology and cognition. Machine learning with 10-fold cross-validation and permutation testing in 729 individuals (aged 8 to 22 years; mean [SD] age, 15.1 [3.3] years; 343 females [46%]) revealed significant association with general psychopathology levels (r = 0.24, P < .001) and cognition (r = 0.39, P < .001). A brain white matter pattern reflecting frontotemporal connectivity and crossing fibers in the uncinate fasciculus was the most associated feature for both traits. Univariate analysis across a range of clinical domains and cognitive test scores confirmed its transdiagnostic importance. Both the general psychopathology (16%; SE, 0.095; P = .05) and cognitive (18%; SE, 0.09; P = .01) factor were heritable and showed a negative genetic correlation. Dimensional and heritable general cognitive and psychopathology factors are associated with specific patterns of white matter properties, suggesting that dysconnectivity is a transdiagnostic brain-based phenotype in individuals with increased susceptibility and symptoms of psychiatric disorders.

The Effect of Poplar PsnGS1.2 Overexpression on Growth, Secondary Cell Wall, and Fiber Characteristics in Tobacco.

The glutamine synthetase (GS1) is a key enzyme that catalyzes the reaction of glutamate and ammonia to produce glutamine in the nitrogen (N) metabolism. Previous studies on GS1s in several plant species suggest that overexpression of GS1s can enhance N utilization, accelerate plant vegetative growth, and change wood formation. In this study, we isolated a GS1 gene, termed PsnGS1.2, from Populus simonii × Populus nigra. This gene was expressed at a higher level in roots, and relatively lower but detectable levels in xylem, leaves and phloem of P. simonii × P. nigra. The protein encoded by PsnGS1.2 is primarily located in the cytoplasm. Overexpression of PsnGS1.2 in tobacco led to the increased GS1 activity and IAA content, the augmented N assimilation, and the enlarged leaves with altered anatomical structures. These changes presumably promoted photosynthetic, growth, and biomass productivity. It was noteworthy that the secondary cell walls and fiber characteristics changed remarkably in PsnGS1.2 transgenic tobacco. These changes aligned well with the altered expression levels of the genes involved in fiber development, secondary cell wall component biosynthesis, IAA biosynthesis, amino acid transport, and starch breakdown. Taken together, the results from our study suggest that catalytic functions of PsnGS1.2 on N assimilation and metabolism in transgenic tobacco had significant effects on vegetative growth, leaf development, and secondary cell wall formation and properties through acceleration of photosynthesis and IAA biosynthesis, and redirection of carbon flux to synthesis of more cellulose and hemicellulose.

Effect of carbon fiber as secondary filler on the electrical, thermal and rheological properties of carbon fiber/polypropylene composites

Abstract In this study, hybrid composites based on carbon fiber (CF) and polypropylene (PP) were fabricated by melt mixing techniques. The composite with optimum fiber length (8 mm) was chosen as a reference material, and to it, CF of various lengths (6 mm, 100 μm, 60 μm and 100 nm) were added as secondary filler. To understand the synergism effect of these fibers, electrical, rheological, thermal and morphological properties of composites were studied. The surface resistivity of the neat PP is in the order of 1017 ohm/square. It is observed that surface resistivity of a single fiber filled composite is in the range of 104 ohm/square, while it further decreased by three-fold (101 ohm/square) in the case of secondary fiber filled composites, indicating that the electrical network remains intact. Thermal analysis shows variation in crystallization of hybrid composites that can correlate to the lengths of secondary fibers. The rheological analysis shows that the frequency dependence of storage modulus (G′) and loss modulus (G″) in the lower frequency region indicates an elastic solid like behavior of these composites. The morphological behavior showed that the CFs are well dispersed and form a good adhesion with the polymer matrix.

Cladistic analysis of some taxa in Malvaceae s.l. “Core Malvales” based on anatomical characteristics

Malvaceae s.l. “Core Malvales” which in their broad circumscription include members of four traditional families; Malvaceae s.s., Bombacaceae, Sterculiaceae and Tiliaceae. The aim of the present study is to evaluate the use of stem, petiole and lamina anatomical characters in analyzing the phylogenetic relationships among 39 studied taxa from Malvaceae s.l. in addition to one representative of Elaeocarpaceae as outgroup through the parsimony analysis using upgraded WinClada and TNT cladistics programs. The anatomy in cross section of stem, petiole and lamina of the 40 studied taxa of Core Malvales were examined by light microscope and photos were taken. The different anatomical characters are discussed and revealed that certain synapomorphic diagnostic characters has great taxonomic values which in turn used for analyzing the phylogenetic relationships between the studied taxa. These characters viz. (petiole outline and vascular system, cuticle thickness, diverse shapes of secondary phloem fibers, presence and types of crystals and trichomes, gossypol gland, resin ducts, tanniferous cells, star-shaped idioblasts, vessels size and distribution, anomalous xylem structure, extrafloral nectaries, ...). Our results of the phylogenetic analysis conducted from the cladogram (rooted tree) based on 44 anatomical characters and 111 character states strongly support the monophyly of family Malvaceae s.s. while, the other three families are para- or polyphyletic. It shows, also the graduation of the taxa under study in relation to the outgroup; from Tiliaceae and Sterculiaceae directly attached to the tree (ancestor) while taxa from Bombacaceae and Malvaceae are far away from the root of the tree with little deviation. This indicates that Tiliaceae is the most primitive family followed by Sterculiaceae, Bombacaceae ending recently by the most advanced family Malvaceae. Our results agree to some extent with APG IV classification in transferring Elaeocarpaceae to order Oxalidales instead of Malvales also agree with other worker in transferring Gossypium and Lagunaria in family Sterculiaceae while transferring Dombeya to family Tiliaceae. For more accurate assignment of Malvaceae s.l. still more studies on a large number of taxa are needed.

Получение теплоизоляционных материалов на основе вторичного целлюлозного волокна

Получение теплоизоляционных материалов на основе вторичного целлюлозного волокна

HOXC13 and HSP27 Expression in Skin and the Periodic Growth of Secondary Fiber Follicles from Longdong Cashmere Goats Raised in Different Production Systems.

This experiment was conducted to identify periodic changes in secondary follicles (SFs) over one year of extensive (grazed) and intensive (housed and fed supplement) farming of Longdong cashmere goats. One-year old goats (n=24, 12 extensively fed and 12 intensively fed) were studied. The diameter, depth, density, activity, and ultra-structural features of SFs were assessed using light microscopy and transmission electron microscopy. HOXC13 and HSP27 expression were studied using immunohistochemistry and immunofluorescence method. The anagen stage in the extensively grazed goats was from April to September, but was longer (April to October) in the housed, supplementary fed group. The depth and activity of the SF in anagen and catagen differed (P<0.05) between the groups. HSP27 and HOXC13 protein were present in both the epidermis and dermis, with HSP27 immunoreactivity highest in the hair shaft (HS), outer root sheath (ORS) and inner root sheath (IRS). HOXC13 expression was prominent in both the eprdermis and ORS. HSP27 and HOXC13 expression were prominent during anagen, and less so during catagen and telogen. In anagen, HSP27 expression in the HS, IRS, and ORS of the extensively fed group was higher than in the intensively fed group (p<0.05). In contrast, HOXC13 expression in HS, IRS and ORS of the extensively fed group was lower than in the intensively fed group (P<0.05). This suggests the growth of cashmere is influenced by nutrition and that housed goats could be used in cashmere production. Anat Rec, 301:742-752, 2018. © 2017 Wiley Periodicals, Inc.

Mapping of recent brachiopod microstructure: A tool for environmental studies.

Shells of brachiopods are excellent archives for environmental reconstructions in the recent and distant past as their microstructure and geochemistry respond to climate and environmental forcings. We studied the morphology and size of the basic structural unit, the secondary layer fibre, of the shells of several extant brachiopod taxa to derive a model correlating microstructural patterns to environmental conditions. Twenty-one adult specimens of six recent brachiopod species adapted to different environmental conditions, from Antarctica, to New Zealand, to the Mediterranean Sea, were chosen for microstructural analysis using SEM, TEM and EBSD. We conclude that: 1) there is no significant difference in the shape and size of the fibres between ventral and dorsal valves, 2) there is an ontogenetic trend in the shape and size of the fibres, as they become larger, wider, and flatter with increasing age. This indicates that the fibrous layer produced in the later stages of growth, which is recommended by the literature to be the best material for geochemical analyses, has a different morphostructure and probably a lower organic content than that produced earlier in life. In two species of the same genus living in seawater with different temperature and carbonate saturation state, a relationship emerged between the microstructure and environmental conditions. Fibres of the polar Liothyrella uva tend to be smaller, rounder and less convex than those of the temperate Liothyrella neozelanica, suggesting a relationship between microstructural size, shell organic matter content, ambient seawater temperature and calcite saturation state.

Neonatal and Juvenile Ocular Development in Sprague-Dawley Rats: A Histomorphological and Immunohistochemical Study.

As in many altricial species, rats are born with fused eyelids and markedly underdeveloped eyes. While the normal histology of the eyes of mature rats is known, the histomorphological changes occurring during postnatal eye development in this species remain incompletely characterized. This study was conducted to describe the postnatal development of ocular structures in Sprague-Dawley (SD) rats during the first month of age using histology and immunohistochemistry (IHC). Both eyes were collected from 51 SD rats at 13 time points between postnatal day (PND)1 and PND30. Histologic examination of hematoxylin and eosin-stained sections was performed, as well as IHC for cleaved-caspase-3 and terminal deoxynucleotidyl transferase dUTP nick-end labeling (TUNEL) to evaluate apoptosis, and IHC for Ki-67 and phospho-histone-H3 to evaluate cell proliferation. Extensive ocular tissue remodeling occurred prior to the eyelid opening around PND14 and reflected the interplay between apoptosis and cell proliferation. Apoptosis was particularly remarkable in the maturing subcapsular anterior epithelium of the lens, the inner nuclear and ganglion cell layers of the developing retina, and the Harderian gland, and was involved in the regression of the hyaloid vasculature. Nuclear degradation in the newly formed secondary lens fibers was noteworthy after birth and was associated with TUNEL-positive nuclear remnants lining the lens organelle-free zone. Cell proliferation was marked in the developing retina, cornea, iris, ciliary body and Harderian gland. The rat eye reached histomorphological maturity at PND21 after a rapid phase of morphological changes characterized by the coexistence of cell death and proliferation.

Differential response of tossa jute (Corchorus olitorius) submitted to water deficit stress

We aimed towards investigating the effects of water deficit stress (WDS) on phenotypic traits, leaf gas exchange, water relations, secondary metabolite profile and fibre properties of six tossa jute (Corchorus olitorius) genotypes grown under control or water withholding conditions. Root length, root weight, stem weight and whole biomass were reduced significantly (p<0.05) in susceptible genotypes but remain unaltered in tolerant genotypes following WDS. The tolerant genotypes showed significantly higher (p<0.05) photosynthetic carbon assimilation (PCA) and water use efficiency (WUE) along with significant reduction (p<0.05) in stomatal conductance (SC), transpiration rate (TR) and vapour pressure deficit (VPD) as compared to susceptible genotypes after WDS. Tolerant genotypes exhibited significantly higher (p<0.05) % RWC as compared to susceptible plants following WDS. Polyphenol and flavonoid content were significantly increased (p<0.05) in tolerant and susceptible genotypes respectively following WDS. Susceptible plants exhibited significantly reduced (p<0.05) proline content as compared to tolerant genotypes. Number of phytochemotypes identified by GC–MS showed 46% and 81% increase in tolerant and susceptible groups respectively, after prolonged WDS. Major phytochemical groups in tolerant genotypes under WDS were ketone, acyclic diterpene alcohol, steroid/sterol, heterocyclic compound, alicyclic hydrocarbon, thiophenol and fatty acid ester. Whereas, the susceptible genotypes exhibited steroid/sterol, acyclic diterpene alcohol, alcohol and heterocyclic compound as the major phytochemical groups under WDS. Tolerant genotypes showed significantly higher (p<0.05) fibre strength as compared to susceptible plants under stress. Our results show identifiable traits manifested by the tolerant and susceptible tossa jute genotypes under WDS which could therefore be utilized successfully for future selection and breeding programs, crop improvement initiatives and production of new varieties having optimum potential toward water deficit stress adaptation.

Printability of papers recycled from toner and inkjet-printed papers after deinking and recycling processes.

In our contemporary world, while part of the fibers used in the paper industry is obtained from primary fibers such as wood and agricultural plants, the rest is obtained from secondary fibers from waste papers. To manufacture paper with high optical quality from fibers of recycled waste papers, these papers require deinking and bleaching of fibers at desired levels. High efficiency in removal of ink from paper mass during recycling, and hence deinkability, are especially crucial for the optical and printability quality of the ultimate manufactured paper. In the present study, deinkability and printability performance of digitally printed paper with toner or inkjet ink were compared for the postrecycling product. To that end, opaque 80 g/m2 office paper was digitally printed under standard printing conditions with laser toner or inkjet ink; then these sheets of paper were deinked by a deinking process based on the INGEDE method 11 p. After the deinking operation, the optical properties of the obtained recycled handsheets were compared with unprinted (reference) paper. Then the recycled paper was printed on once again under the same conditions as before with inkjet and laser printers, to monitor and measure printing color change before and after recycling, and differences in color universe. Recycling and printing performances of water-based inkjet and toner-based laser printed paper were obtained. The outcomes for laser-printed recycled paper were better than those for inkjet-printed recycled paper. Compared for luminosity Y, brightness, CIE a* and CIE b* values, paper recycled from laser-printed paper exhibited higher value than paper recycled from inkjet-printed paper.

Histological validation of diffusion MRI fiber orientation distributions and dispersion

Diffusion magnetic resonance imaging (dMRI) is widely used to probe tissue microstructure, and is currently the only non-invasive way to measure the brain's fiber architecture. While a large number of approaches to recover the intra-voxel fiber structure have been utilized in the scientific community, a direct, 3D, quantitative validation of these methods against relevant histological fiber geometries is lacking. In this study, we investigate how well different high angular resolution diffusion imaging (HARDI) models and reconstruction methods predict the ground-truth histologically defined fiber orientation distribution (FOD), as well as investigate their behavior over a range of physical and experimental conditions. The dMRI methods tested include constrained spherical deconvolution (CSD), Q-ball imaging (QBI), diffusion orientation transform (DOT), persistent angular structure (PAS), and neurite orientation dispersion and density imaging (NODDI) methods. Evaluation criteria focus on overall agreement in FOD shape, correct assessment of the number of fiber populations, and angular accuracy in orientation. In addition, we make comparisons of the histological orientation dispersion with the fiber spread determined from the dMRI methods. As a general result, no HARDI method outperformed others in all quality criteria, with many showing tradeoffs in reconstruction accuracy. All reconstruction techniques describe the overall continuous angular structure of the histological FOD quite well, with good to moderate correlation (median angular correlation coefficient > 0.70) in both single- and multiple-fiber voxels. However, no method is consistently successful at extracting discrete measures of the number and orientations of FOD peaks. The major inaccuracies of all techniques tend to be in extracting local maxima of the FOD, resulting in either false positive or false negative peaks. Median angular errors are ∼10° for the primary fiber direction and ∼20° for the secondary fiber, if present. For most methods, these results did not vary strongly over a wide range of acquisition parameters (number of diffusion weighting directions and b value). Regardless of acquisition parameters, all methods show improved successes at resolving multiple fiber compartments in a voxel when fiber populations cross at near-orthogonal angles, with no method adequately capturing low to moderate angle (<60°) crossing fibers. Finally, most methods are limited in their ability to capture orientation dispersion, resulting in low to moderate, yet statistically significant, correlation with histologically-derived dispersion with both HARDI and NODDI methodologies. Together, these results provide quantitative measures of the reliability and limitations of dMRI reconstruction methods and can be used to identify relative advantages of competing approaches as well as potential strategies for improving accuracy.

QTL analysis of four main stem bark traits using a GBS-SNP-based high-density genetic map in ramie

Ramie fiber extracted from ramie stem bark (RSB) is a highly important natural fiber, and therefore, RSB is an economically important plant organ. The genetic basis of RSB traits is poorly understood. In the present study, fiber yield and three RSB traits (bark thickness, bark weight, and fiber output ratio) were subject to quantitative trait locus (QTL) analysis using an F2 agamous line population derived from two ramie varieties (Qingdaye and Zhongzhu 1). A total of 4338 high-quality single nucleotide polymorphisms were identified using the genotyping-by-sequencing technique and were subsequently used to construct a high-density genetic map spanning 1942.9 cM. Thereafter, QTL analysis identified five, two, four, and four QTLs for bark thickness, bark weight, fiber output ratio, and fiber yield, respectively. A 5.1 cM region that corresponded to a QTL for bark thickness (qBT4a) contained 106 candidate genes, and the Zhongzhu 1 allele of one of the genes, a putative MYB gene (evm.model.scaffold7373.133_D1), included a 760-bp insertion that caused premature termination, thereby producing a protein that lacked part of the MYB domain. Because MYB transcription factors play central roles in regulating the development of secondary cellular walls and fiber biosynthesis, we propose evm.model.scaffold7373.133_D1 as a likely candidate gene for qBT4a.

Thermal conductivity of biomimetic leaf composite

The venous morphology of a typical plant leaf affects its mechanical and thermal properties. Such a material could be considered as a fiber reinforced composite structure where the veins and the rest of the leaf are considered as two materials having highly contrast mechanical and thermal properties. The variegated venations found in nature is idealized into three principal fibers—the central mid-fiber corresponding to the mid-rib, straight parallel secondary fibers attached to the mid-fiber representing the secondary veins, and then another set of parallel fibers emanating from the secondary fibers mimicking the tertiary veins of a typical leaf. This paper addresses the in-plane thermal conductivity of such a composite by considering such a venous fiber morphology embedded in a matrix material. We have considered two cases, fibers having either higher or lower conductivity respect to the matrix. The tertiary fibers do not interconnect the secondary fibers in our present study. We carry out finite element based computational investigation of the thermal conductivity of these composites under uniaxial thermal gradients and study the effect of different fiber architectures. To this end, we use two broad types of architectures both having similar central main fiber but differing in either having only secondary fibers or additional tertiary fibers. The fiber and matrix volume fractions are kept constant and a comparative parametric study is carried out by varying the inclination of the secondary fibers. We find the heat conductivity in the direction of the main fiber (Y direction) increases significantly as the fiber angle of the secondary increases. Furthermore, for composite with metal fibers, the conductivity in the Y direction is further enhanced when composite is manufactured by having secondary fibers forming a closed cell structure. However, for composite with ceramic fibers, the conductivity of the composite in the Y direction is little affected by having secondary fibers closed. An opposite behavior is observed when considering conductivity of the composite in the X direction. The conductivity of the composite in the X direction is reduced with increase in the angle of the secondary fibers. Higher conductivity in the X direction is achieved for composite with no closed cells for composites with metal fibers. The results also indicate that for composites with the constant fiber volume fraction, morphology of tertiary fibers may not significantly alter material conductivities. In conclusion, introducing a leaf-mimicking topology in fiber architecture can provide significant additional degrees of tunability in design of these composite structures.

Functional identification of an EXPA gene (NcEXPA8) isolated from the tree Neolamarckia cadamba

ABSTRACTAs a class of important cell growth regulators, expansins have been studied for over 20 years. Since Neolamarckia cadamba (Roxb.) Bosser was praised as a ‘miraculous tree’ at the World Forestry Congress in 1972 due to its rapid growth. A lot of research has been carried out to uncover the underlying mechanisms of this rapid growth. Based on previous findings and our research, we hypothesized that expansins may play an important role in such growth. Quantitative real-time polymerase chain reaction (qRT-PCR) analysis revealed that the N. cadamba expansin family member NcEXPA8 is highly expressed in all four young tissues, particularly in the cambium region, suggesting that NcEXPA8 acts as a key regulator of secondary growth in this gene family. Overexpression of NcEXPA8 in Arabidopsis thaliana increased the diameter and height of the main stem. It also promoted interfascicular fiber cell elongation and cell-wall thickness but did not alter the cellulose content in the cell wall. These results suggested that expansins act as activators during secondary fiber cell elongation during tip growth to promote plant growth.