Mexican Bark Paper: Evidence of History of Tree Species Used and Their Fiber Characteristics

Mexican Bark Paper: Evidence of History of Tree Species Used and Their Fiber Characteristics. The use of bark fibers (secondary phloem) for the manufacture of the Mexican bark paper called amate can be traced back to the pre–Hispanic period. This paper was used extensively during this period, and for the last four decades has been produced as a handicraft by the Ñahñus of San Pablito village in the Sierra Norte de Puebla region of México. Due to the high demand for this product, new species are now used as a source of bark and specific phases of the traditional production technique have been modified. The focus of this study was to register all the species that have been used for bark paper manufacturing, both traditionally and more recently, and to analyze their fiber characteristics, mainly fiber length and lignin content. The main questions addressed by this study were: a) Which species have been used for bark paper production, both prior to and following its commercialization as a handicraft? b) Which anatomical and histochemical fiber characteristics of these species enable their use for bark paper production, regardless of taxa? And c) is there a relationship between the adoption and use of new species and recent changes in traditional paper making techniques? Based on an ethnobotanical study, a list of 13 species used for bark paper production was compiled and bark samples from each species were collected for phloem anatomical and histochemical analysis. Artisans and local healers were also asked to determine the main characteristics of each fiber and paper type. The results demonstrate that bark from currently used species differs anatomically and histochemically from species used during the pre–Hispanic period and until a few decades ago, and in terms of the quality assessed by local healers and artisans. Among other characteristics, the fibers of the new species have higher lignin content than the traditional ones, and this constitutes the main reason behind the modification of certain phases of the traditional paper making process.     

Fiber properties of several species of agavaceae from the Southwestern United States and Northern Mexico

Hard fibers are tissues obtained by decorticating leaves of various monocots, including sisal and abaca. These fibers have traditionally been used in cordage applications (rope, burlap, etc.), but they are also pulped and used in the paper industry for making specialty papers including currency, tea bags, and other products requiring high tensile strength. We examined fiber properties of several genera of Agavaceae from the southwestern United States and northern Mexico to determine their potential for paper making. Leaf samples of species ofAgave, Dasylirion, Hesperaloe, Nolina, and Yucca were macerated and fiber cell length, width, and wall thickness were measured. Several species ofHesperaloe andYucca have fibers that are as long or longer (>3 mm) and narrower (<20 µ) than those of sisal. Species ofAgave, Dasylirion, and,Nolina have shorter fibers (mostly 1.5 mm). Species ofHesperaloe andYucca would appear to be most suitable for paper making.     

Jaw muscle fiber type distribution in Hawaiian gobioid stream fishes: histochemical correlations with feeding ecology and behavior

Differences in fiber type distribution in the axial muscles of Hawaiian gobioid stream fishes have previously been linked to differences in locomotor performance, behavior, and diet across species. Using ATPase assays, we examined fiber types of the jaw opening sternohyoideus muscle across five species, as well as fiber types of three jaw closing muscles (adductor mandibulae A1, A2, and A3). The jaw muscles of some species of Hawaiian stream gobies contained substantial red fiber components. Some jaw muscles always had greater proportions of white muscle fibers than other jaw muscles, independent of species. In addition, comparing across species, the dietary generalists (Awaous guamensis and Stenogobius hawaiiensis) had a lower proportion of white muscle fibers in all jaw muscles than the dietary specialists (Lentipes concolor, Sicyopterus stimpsoni, and Eleotris sandwicensis). Among Hawaiian stream gobies, generalist diets may favor a wider range of muscle performance, provided by a mix of white and red muscle fibers, than is typical of dietary specialists, which may have a higher proportion of fast-twitch white fibers in jaw muscles to help meet the demands of rapid predatory strikes or feeding in fast-flowing habitats.     

The subunit structure of chromatin fibres

Optimal conditions for studying the ultrastructure of chromatin fibers of histone-containing spermatozoa in thin sections have been determined. Better results for preservation in sperm of the sea cucumber Holothuria tubulosa, have been found than in different frog species studied. The fine structure of chromatin fibers after different treatments was studied by computer methods. A clear superbead structure was found under all conditions which preserve the chromatin fibres. These have a diameter of 30 nm, with superbeads about 33 nm long. In the best preserved cases an additional periodicity of 11 nm along the fibres was found. There is no clear relationship of this periodicity with an eventual solenoidal structure of the chromatin fibers.     

Projection of fibers immunoreactive to an antiserum against gonadoliberin (LHRH) into the pineal stalk of the white-crowned sparrow,Zonotrichia leucophrys gambelii

Summary We have demonstrated a bundle of fibers, immunoreactive to an antiserum against gonadoliberin (luteinizing hormone-releasing hormone), that projects into the pineal stalk of photostimulated male Z. l. gambelii, a photoperiodic passerine species. These fibers have their origin in the dorsal division of the column of gonadoliberin-positive perikarya that extends caudodorsally from the ventromedial preoptic area to the level of the anterior commissure. After entering the habenula these fibers can be traced into the pineal stalk. This bundle is of interest because it apparently has not previously been reported in birds, and further, because the pineal body of this species is not known to have a role in the photoperiodic induction of increased rates of release of gonadotropins. Relationships of this bundle to other components of the gonadoliberin system are described briefly.     

Some aspects of the structural organization of the arthropod ganglia

Summary This paper deals with the fine structure of the abdominal ganglia of several species of arthropods belonging to the classes Arachnida, Crustacea, Myriapoda and Insecta. The tissues were fixed in osmium tetroxide and embedded in n-butyl methacrylate or fixed in potasium permanganate and embedded in a mixture of X 133/2097 and Araldite.A comparative study was made in order to discriminate between those structural characteristics of the nervous system appearing only in determined taxonomic groups and those belonging to a fundamental plan common to the whole Phylum. This work covers the morphology of neurons, glial cells, neuropilic nerve fibers and neuronal connections.Most arthropod neurons are pear-shaped with only one prolongation and the nucleus is located in the center of the soma, enveloped by two membranes showing numerous pores. Cisternae of the ER have frequently been observed in continuity with this nuclear envelope. After osmic fixation the nuclear content appears to consist of small dense granules distributed at random in the nucleoplasm. In addition to these small perticles there are, in some species, large chromatin blocks. The use of Permanganate as fixative introduces important changes in the nuclear aspect; most of the nuclei look washed and the nuclear content acquires an homogeneous appearance.The cytoplasm of the neurons contains a complex system of internal membranes consisting of cisternae and tubuli of the ER system, lamellae of the Golgi complex and invaginations of the plasma membrane. In most species the elements of the ER system are distributed at random in the cytoplasm but in the neurons of Bothriurus bonariensis there are parallel aggregations of membranes similar to the Nissl bodies found in vertebrates.It was found in some of the species studied (Armadillidium vulgare and Lithobius Sp.) that the internal membrane system of the nerve cells is mainly represented by Golgi elements while the ER system seems to be poorly developed.Besides the membranous components, the neuronal cytoplasm contains mitochondria, multivesicular bodies and dense granules of neurosecretory material.Neuroglial cells are mainly characterized by their nuclear structure. After the action of osmium tetroxide, glial nuclei show irregular masses of chromatin inmersed in a nucleoplasm of low electron density. In permanganate fixed material these chromatin blocks appear as blank spaces.In the cytoplasm of these cells there are mitochondria, membranes pertaining to the ER system and elements of the Golgi complex but in some of the species studied gliofibrils and granules of pigment were found.Three main types of neuroglial cells have been recognized in an arthropod ganglia. These are: subcapsular glial cells, neuron satellites and nerve fiber satellites.The neuropile occupies the central region of the ganglion and consists of a great number of nerve fibers intermingled with glial processes. The neuropilic n. fibers consistently show profiles of ER membranes and tubuli pertaining to the ER system. In some of these fibers the ER reaches a high degree of development. In Armadillidium there is a special type of n. fiber containing a regular sequence of transversally oriented cisternae. Arthropod fibers sometimes contain thin parallel filaments as well as typical ER elements.Mitochondria, small vesicles and dense granules are commonly found within the neuroplasm of the neuropilic fibers. It is important to note that in arthropods, microvesicles are not restricted to the terminal region of the nerve fibers but that they may also occur all along the fibers.Arthropod neurons are enveloped by a glial insulating capsule and therefore interneuron contacts may only occur at neuropile level. These contacts are of three different morphological types: cross contacts, longitudinal contacts and end-knob contacts. At the level of longitudinal and cross contacts the neuroplasm shows no increase in the number of microvesicles or mitochondria. In the end-knob contacts, on the contrary, large numbers of microvesicles appear concentrated in the pre-synaptic fiber only, and occasionally in both fibers the pre-synaptic and the post-synaptic.It is maintained that funcional interneuron connections may result not only from contacts between fibers containing vesicles, but also between fibers in which vesicles are absent.     

Selection of Bacillus species for targeted in situ release of prebiotic galacto-rhamnogalacturonan from potato pulp in piglets

We have previously shown that galacto-rhamnogalacturonan fibers can be enzymatically extracted from potato pulp and that these fibers have potential for exerting a prebiotic effect in piglets. The spore-forming Bacillus species are widely used as probiotics in feed supplements for pigs. In this study, we evaluated the option for further functionalizing Bacillus feed supplements by selecting strains possessing the enzymes required for extraction of the potentially prebiotic fibers. We established that it would require production and secretion of pectin lyase and/or polygalacturonase but no or limited secretion of galactanase and β-galactosidase. By screening a library of 158 Bacillus species isolated from feces and soil, we demonstrated that especially strains of Bacillus amyloliquefaciens, Bacillus subtilis, and Bacillus mojavensis have the necessary enzyme profile and thus the capability to degrade polygalacturonan. Using an in vitro porcine gastrointestinal model system, we revealed that specifically strains of B. mojavensis were able to efficiently release galacto-rhamnogalacturonan from potato pulp under simulated gastrointestinal conditions. The work thus demonstrated the feasibility of producing prebiotic fibers via a feed containing Bacillus spores and potato pulp and identified candidates for future in vivo evaluation in piglets.

     

Monoamine-containing structures in the intestines of bivalve molluscs and a polychaete annelid revealed by fluorescence histochemistry

Summary Monoamine-containing elements in the intestines of Bivalvia and Polychaeta species have been found by use of histochemical fluorescence methods according to Falck and Furness. Catecholamine-containing perikarya and fibers are seen within the epithelium and subepithelial layers of the midgut of the bivalves Mytilus edulis, Mya arenaria, Arctica islandica, as well as the polychaete Harmothoe imbricata. In addition, intraepithelial cell bodies and fibers containing serotonin-like substance are present in Mytilus edulis. Results obtained with the Furness method, applied earlier to vertebrates, correlate with those obtained with the Falck method.     

Morphological and histochemical characterization of the pectoral fin muscle of batoids

Batoids differ from other elasmobranch fishes in that they possess dorsoventrally flattened bodies with enlarged muscled pectoral fins. Most batoids also swim using either of two modes of locomotion: undulation or oscillation of the pectoral fins. In other elasmobranchs (e.g., sharks), the main locomotory muscle is located in the axial myotome; in contrast, the main locomotory muscle in batoids is found in the enlarged pectoral fins. The pectoral fin muscles of sharks have a simple structure, confined to the base of the fin; however, little to no data are available on the more complex musculature within the pectoral fins of batoids. Understanding the types of fibers and their arrangement within the pectoral fins may elucidate how batoid fishes are able to utilize such unique swimming modes. In the present study, histochemical methods including succinate dehydrogenase (SDH) and immunofluoresence were used to determine the different fiber types comprising these muscles in three batoid species: Atlantic stingray (Dasyatis sabina), ocellate river stingray (Potamotrygon motoro) and cownose ray (Rhinoptera bonasus). All three species had muscles comprised of two muscle fiber types (slow-red and fast-white). The undulatory species, D. sabina and P. motoro, had a larger proportion of fast-white muscle fibers compared to the oscillatory species, R. bonasus. The muscle fiber sizes were similar between each species, though generally smaller compared to the axial musculature in other elasmobranch fishes. These results suggest that batoid locomotion can be distinguished using muscle fiber type proportions. Undulatory species are more benthic with fast-white fibers allowing them to contract their muscles quickly, as a possible means of escape from potential predators. Oscillatory species are pelagic and are known to migrate long distances with muscles using slow-red fibers to aid in sustained swimming.     

Ultrastructure variation in the spermatozoa of Pseudopaludicola frogs (Amphibia,Anura, Leptodactylidae), with brief comments on its phylogenetic relevance

The taxonomic history of the small frogs of the genus Pseudopaludicola from South America has been controversial. Phylogenetic inferences based on molecular data have identified four Pseudopaludicola clades, correlating with the known variation in karyotypes (2n = 22, 20, 18, and 16). In this study, the ultrastructure of the spermatozoa was analyzed in 12 species of the Pseudopaludicola, with the aim of describing their morphology and identifying characters that may contribute to a better understanding of the phylogenetic relationships. The spermatozoa presented marked differences in tail structures. The tails of the spermatozoa of the species with 2n = 22 chromosomes (Pseudopaludicola sp. 1 [P. pusilla group], Pseudopaludicola falcipes, P. mineira, and Pseudopaludicola saltica), as well as Pseudopaludicola ameghini and Pseudopaludicola ternetzi (2n=20), have juxta‐axonemal fibers, undulating membranes and axial fibers. In contrast, in the species with 2n = 18 (P. facureae, P. giarettai, Pseudopaludicola canga, P. atragula, and Pseudopaludicola sp. 2) and 2n = 16 (Pseudopaludicola mystacalis), there are no evident axial or juxta‐axonemal fibers, but a paraxonemal rod with a thick undulating membrane, which is shorter than that found among Pseudopaludicola species. The ultrastructural morphological differences observed in the spermatozoa of these species may be phylogenetically informative, given that they coincide with the consensus phylogeny of the group and appear to represent a progressive simplification of the spermatozoon. J. Morphol. 276:1495–1504, 2015. © 2015 Wiley Periodicals, Inc.     

Distribution of FMRFamide-like immunoreactivity in the brain,retina and nervus terminalis of the sockeye salmon parr,Oncorhynchus nerka

Summary Neurons displaying FMRFamide(Phe-Met-Arg-Phe-NH₂)-like immunoreactivity have recently been implicated in neural plasticity in salmon. We now extend these findings by describing the extent of the FMRF-like immunoreactive (FMRF-IR) system in the brain, retina and olfactory system of sockeye salmon parr using the indirect peroxidase anti-peroxidase technique. FMRF-IR perikarya were found in the periventricular hypothalamus, mesencephalic laminar nucleus, nucleus nervi terminalis and retina (presumed amacrine cells), and along the olfactory nerves. FMRF-IR fibers were distributed throughout the brain with highest densities in the ventral area of the telencephalon, in the medial forebrain bundle, and at the borders between layers III/IV and IV/V in the optic tectum. High densities of immunoreactive fibers were also observed in the area around the torus semicircularis, in the medial hypothalamus, median raphe, ventromedial tegmentum, and central gray. In the retina, immunopositive fibers were localized to the inner plexiform layer, but several fiber elements were also found in the outer plexiform layer. The olfactory system displayed FMRF-IR fibers in the epithelium and along the olfactory nerves. These findings differ from those reported in other species as follows: (i) FMRF-IR cells in the retina have not previously been reported in teleosts; (ii) the presence of FMRF-IR fibers in the outer plexiform layer of the retina is a new finding for any species; (iii) the occurrence of immunopositive cells in the mesencephalic laminar nucleus has to our knowledge not been demonstrated previously.     

The potential of photosynthetic aquatic species as sources of useful cellulose fibers—a review

Photosynthetic aquatic species, i.e., micro- and macroalgae and fresh or salt water plants, contain cellulose or other fibrous materials potentially suitable for paper making. Photosynthetic aquatic species having cellulosic or fibrous characteristics necessary for paper production were reviewed. These characteristics include overall fiber content, fiber size and morphology, and fiber composition. Several species of algae and aquatic plants are reported to possess cellulose in quantities greater than 10 % of total dry weight, and in general, the cellulose content in aquatic species is lower than that of most wood species. Commercial application of these aquatic algal or plant materials has been limited to simple milling, and no commercial applications utilizing processes to isolate the cellulosic fibers from these materials have yet been found.     

Transmission X-ray microscopy of spider dragline silk

We have investigated the structure of spider silk fibers from two different Nephila species and three different Araneus species by transmission X-ray microscopy (TXM). Single fibers and double fibers have been imaged. All images are in agreement with a homogenous density on length scales between the fiber diameter and the resolution of the instrument, which is about 25 nm.     

The Spermatid Nucleus in Two Species of Grasshopper

The nuclear changes accompanying spermatid elongation have been studied in two species of grasshopper, Dissosteira carolina and Melanoplus femur-rubrum. Testes were fixed in 1 per cent buffered OsO₄, imbedded in butyl methacrylate, and examined as thin sections in the electron microscope. In both species nuclear changes during spermatid development involve (1) an early period, during which the nuclear contents are predominately fibrous; (2) a middle period, characterized by the lateral association of the nuclear fibers to form plates or lamellae which are oriented longitudinally in the major axis of the elongated nucleus; and (3) a late period, involving coalescence of the lamellae into a crystalline body which eventually becomes so dense that all resolvable detail is lost. The fibers seen in the early spermatid nucleus are about 150 A in diameter and so are similar to fibers described from other types of nuclei. The thickness of the lamellae varies from about 150 A when first formed to 70 A during the later stages. The lack of evident chromosomal boundaries in the spermatid nucleus makes it difficult to relate either the fibers or lamellae to more familiar aspects of chromosome structure. We see no apparent reason to consider that the fiber alignment described here is related to conventional chromosome pairing.     

Musculature in polychaetes: comparison of Myrianida prolifera (Syllidae) and Sphaerodoropsis sp. (Sphaerodoridae)

Abstract. The relationship of the polychaete taxa Syllidae and Sphaerodoridae within Phyllodocida is still unresolved: phylogenetic analyses either show them as sister groups or more widely separated. The present article aims to provide information about the structure of the muscular system that could be essential for understanding their relationship. A crucial point is whether the body wall contains circular muscles, which has recently been shown to be absent in more taxa than previously known. The F-actin filaments in members of Myrianida prolifera (Syllidae) and Sphaerodoropsis sp. (Sphaerodoridae) were labeled with phalloidin and their three-dimensional relationships reconstructed by means of confocal laser scanning microscopy. Among the noteworthy differences that emerged between the species are (1) members of M. prolifera possess four, those of Sphaerodoropsis sp. eight, longitudinal muscle strands; (2) the body wall in M. prolifera contains transverse fibers in a typical, supralongitudinal position, while in Sphaerodoropsis sp., corresponding fibers lie beneath the longitudinal strands; (3) pro- and peristomium in M. prolifera have no distinct F-actin fibers, while five longitudinal pairs and three single transverse muscular fibers shape the anterior end in Sphaerodoropsis sp.; (4) the proventricle of M. prolifera comprises primarily radial muscle fibers arranged in distinct rows, while in Sphaerodoropsis sp. the axial proboscis consists of longitudinal and circular fibers and radial fibers are lacking; (5) in M. prolifera, the proximal and distal sections of the two anteriormost pairs of dorsal cirri possess longitudinal myofilaments, which are separate from the body wall musculature; by contrast, all appendages in Sphaerodoropsis sp. do not; (6) both species have bracing muscles: in M. prolifera they are positioned above the longitudinal fibers, whereas in Sphaerodoropsis sp. they are uniquely positioned between longitudinal and sublongitudinal transverse fibers. These results do not support a sister-group relationship of Syllidae and Sphaerodoridae. In addition, Sphaerodoropsis sp. is yet another example in the list of polychaetes lacking typical circular muscles in the body wall.     

The global potential for Agave as a biofuel feedstock

Large areas of the tropics and subtropics are too arid or degraded to support food crops, but Agave species may be suitable for biofuel production in these regions. We review the potential of Agave species as biofuel feedstocks in the context of ecophysiology, agronomy, and land availability for this genus globally. Reported dry biomass yields of Agave spp., when annualized, range from <1 to 34 Mg ha^?1 yr^?1 without irrigation, depending on species and location. Some of the most productive species have not yet been evaluated at a commercial scale. Approximately 0.6 Mha of land previously used to grow Agave for coarse fibers have fallen out of production, largely as a result of competition with synthetic fibers. Theoretically, this crop area alone could provide 6.1 billion L of ethanol if Agave were re‐established as a bioenergy feedstock without causing indirect land use change. Almost one‐fifth of the global land surface is semiarid, suggesting there may be large opportunities for expansion of Agave crops for feedstock, but more field trials are needed to determine tolerance boundaries for different Agave species.     

Down-regulating annexin gene GhAnn2 inhibits cotton fiber elongation and decreases Ca2+ influx at the cell apex

Cotton fiber is a single cell that differentiates from the ovule epidermis and undergoes synchronous elongation with high secretion and growth rate. Apart from economic importance, cotton fiber provides an excellent single-celled model for studying mechanisms of cell-growth. Annexins are Ca²⁺- and phospholipid-binding proteins that have been reported to be localized in multiple cellular compartments and involved in control of vesicle secretions. Although several annexins have been found to be highly expressed in elongating cotton fibers, their functional roles in fiber development remain unknown. Here, 14 annexin family members were identified from the fully sequenced diploid G. raimondii (D₅ genome), half of which were expressed in fibers of the cultivated tetraploid species G. hirsutum (cv. YZ1). Among them, GhAnn2 from the D genome of the tetraploid species displayed high expression level in elongating fiber. The expression of GhAnn2 could be induced by some phytohormones that play important roles in fiber elongation, such as IAA and GA₃. RNAi-mediated down-regulation of GhAnn2 inhibited fiber elongation and secondary cell wall synthesis, resulting in shorter and thinner mature fibers in the transgenic plants. Measurement with non-invasive scanning ion-selective electrode revealed that the rate of Ca²⁺ influx from extracellular to intracellular was decreased at the fiber cell apex of GhAnn2 silencing lines, in comparison to that in the wild type. These results indicate that GhAnn2 may regulate fiber development through modulating Ca²⁺ fluxes and signaling.     

Serological similarity of flagellar and mitotic microtubules

An antiserum to flagellar axonemes from sperm of Arbacia punctulata contains antibodies which react both with intact flagellar outer fibers and with purified tubulin from the outer fibers. Immunodiffusion tests indicate the presence of similar antigenic determinants on outer-fiber tubulins from sperm flagella of five species of sea urchins and a sand dollar, but not a starfish. The antibodies also react with extracts containing tubulins from different classes of microtubules, including central-pair fibers and both A- and B-subfibers from outer fibers of sperm flagella, an extract from unfertilized eggs, mitotic apparatuses from first cleavage embryos, and cilia from later embryos. Though most tubulins tested share similar antigenic determinants, some clear differences have been detected, even, in Pseudoboletia indiana, between the outer-fiber tubulins of sperm flagella and blastular cilia. Though tubulins are "actin-like" proteins, antitubulin serum does not react with actin from sea urchin lantern muscle. On the basis of these observations, we suggest that various echinoid microtubules are built of similar, but not identical, tubulins.     

The Specific Force of Single Intact Extensor Digitorum Longus and Soleus Mouse Muscle Fibers Declines with Aging

In the present study we measured, for the first time, the isometric specific force (SF, force normalized to cross sectional area) generated by single intact fibers from fast- (extensor digitorum longus, EDL) and slow-twitch (soleus) muscles from young adult (2–6), middle-aged (12–14) and old (20–24 month-old) mice. SF has also been measured in single intact flexor digitorum brevis fibers from young mice. Muscle fibers have been classified into fast- or slow-twitch based on the contraction kinetics. Maximum SF recorded in EDL and soleus fibers from young and middle-aged mice did not differ significantly. A significant age-dependent decline in maximum SF was recorded in EDL and soleus fibers from young or middle-aged to old mice. The SF was 377 ± 18, 417 ± 20 and 279 ± 18 kPa for EDL fibers from young, middle-aged and old mice, respectively and 397 ± 17, 405 ± 24 and 320 ± 33 kPa for soleus fibers from age-matched mice, respectively. The frequency needed to elicit maximum force in EDL and soleus fibers from middle-aged to old mice did not differ significantly. In conclusion, the specific force developed by both fast and slow-twitch single intact muscle fibers declines with aging and more significantly in the former. Received: 14 July 2000/Revised: 7 September 2000