Central Cylinder Research Articles

Histological characterization of Passiflora pohlii Mast. root tips cryopreserved using the V-Cryo-plate technique.

Cryopreservation stands out as the main strategy to ensure safe and cost efficient long-term conservation of plant germplasm, especially for biotechnological materials. However, the injuries associated with the procedure may result in structural damage and low recovery rates after cooling. Histological analysis provides useful information on the effects of osmotic dehydration, LN exposure, and recovery conditions on cellular integrity and tissue organization, allowing the determination of the critical steps of the cryopreservation protocol and, thus, the use of optimized treatments. Passiflora pohlii Mast. (Passifloraceae) is a native species from Brazil with potential agronomic interest. Recent studies showed the presence of saponins in its roots, which presented antioxidant activity. The goal of this work was to develop a cryopreservation technique for root tips of in vitro-derived plants of P. pohlii using the V-Cryo-plate technique and to characterize the anatomical alterations that occurred during the successive steps of the protocol. Root tips were excised from in vitro plants and precultured before adhesion to cryo-plates and then treated for different periods with the plant vitrification solutions PVS2 or PVS3. Treatment with PVS2 for 45min resulted in higher recovery (79%) when compared with PVS3 (43%). The greatest number of adventitious roots per cryopreserved explant was also observed after a 45-min exposure to PVS2. Plasmolysis levels were higher in cortical cells of cryopreserved explants treated with PVS2, while pericycle and central cylinder cells were not damaged after this treatment. Thirty days after rewarming, no plasmolysis could be detected, regardless of the experimental conditions.

The Impact of Industrial Pollution on the Stem Anatomical Characteristics of Woody Plant Undergrowth in the City of Dnipro, Ukraine

The paper examines the influence of industrial emissions of sulphur (IV) and nitrogen (IV) oxides on the percentage of stem anatomical characteristics of the autochthonous woody plant species undergrowth of Acer platanoides L. and Fraxinus excelsior L. in the southern industrial zone of the city of Dnipro (Ukraine). It is ascertained, that the ratio of the primary cortex share to the central cylinder share does not change in the stems of annual shoots of the both studied woody plant species when they are exposed to the influence of the toxic gases. However, there are significant changes in the ratio of shares of histological elements in the undergrowth stems of F. excelsior. The use of both absolute and relevant values of anatomic parameters of the plant vegetative organs is needed to analyse the woody plants resistance to technogenic pollution of the environment.

Partitioning k‐space for cylindrical three‐dimensional rapid acquisition with relaxation enhancement imaging in the mouse brain

Three-dimensional rapid acquisition with relaxation enhancement (RARE) scans require the assignment of each phase encode step in two dimensions to an echo in the echo train. Although this assignment is frequently made across the entire Cartesian grid, collection of only the central cylinder of k-space by eliminating the corners in each phase encode dimension reduces the scan time by ~22% with negligible impact on image quality. The recipe for the assignment of echoes to grid points for such an acquisition is less straightforward than for the simple full Cartesian acquisition case, and has important implications for image quality. We explored several methods of partitioning k-space-exploiting angular symmetry in one extreme or emulating a cropped Cartesian acquisition in the other-and acquired three-dimensional RARE magnetic resonance imaging (MRI) scans of the ex vivo mouse brain. We evaluated each partitioning method for sensitivity to artifacts and then further considered strategies to minimize these through averaging or interleaving of echoes and by empirical phase correction. All scans were collected 16 at a time with multiple-mouse MRI. Although all schemes considered could be used to generate images, the results indicate that the emulation of a standard Cartesian echo assignment, by partitioning preferentially along one dimension within the cylinder, is more robust to artifacts. Samples at the periphery of the bore showed larger phase deviations and higher sensitivity to artifacts, but images of good quality could still be obtained with an optimized acquisition protocol. A protocol for high-resolution (40μm) ex vivo images using this approach is presented, and has been used routinely with a success rate of 99% in over 1000 images.

Infection process of Gaeumannomyces graminis var. graminis on the roots and culms of rice

AbstractCrown sheath rot, caused by the ascomycete Gaeumannomyces graminis var. graminis that infects the root and the base of the culm of rice, causes early grains maturation, tiller death and reduced yield. As a paucity of information exists in the literature on the rice‐G. graminis var. graminis interaction at the microscopic level, this study aimed to gain novel insights into the infection process of this pathogen in the root and culm of rice using both light and scanning electron microscopy. In the roots, the fungus initially colonized the epidermal, exodermal and sclerenchyma cells. At 15 days after inoculation (dai), fungal hyphae colonized the cortex and clusters of perithecia were observed in the roots. At 20 dai, the fungus reached the central cylinder, and an intense fungal colonization at the base of the culm was observed that resulted in the formation of a mycelial mat on both adaxial and abaxial surfaces of the leaf sheaths. At 25 dai, fungal growth was noticed in the parenchyma cells, vascular bundles and airspaces. Perithecia emerged through the base of prophyllum and from the first leaf sheath at 30 dai. The results of this study provide new insights into the infection process of G. graminis var. graminis in rice and may help to find better control measures in reducing crown sheath rot development.

The Impact of Industrial Pollution on the Stem Anatomical Characteristics of Woody Plant Undergrowth in the City of Dnipro, Ukraine

The paper examines the influence of industrial emissions of sulphur (IV) and nitrogen (IV) oxides on the percentage of stem anatomical characteristics of the autochthonous woody plant species undergrowth of Acer platanoides L. and Fraxinus excelsior L. in the southern industrial zone of the city of Dnipro (Ukraine). It is ascertained, that the ratio of the primary cortex share to the central cylinder share does not change in the stems of annual shoots of the both studied woody plant species when they are exposed to the influence of the toxic gases. However, there are significant changes in the ratio of shares of histological elements in the undergrowth stems of F. excelsior. The use of both absolute and relevant values of anatomic parameters of the plant vegetative organs is needed to analyse the woody plants resistance to technogenic pollution of the environment.

PHYTOCHEMICAL STUDIES AND PHARMACOGNOSTICAL EVALUATION OF ZINGIBER CASSUMUNAR ROXB

Objective: Zingiber Cassumunar Roxb is a well known medicinal plant employed to cure various diseases were reported to possess good medicinal value in traditional system of medicine. The present investigation deals with microscopic, macroscopic and preliminary phytochemical investigation of rhizome to give clear standards for identification of the drug.Method: For the microscopic evaluation, the powder was soaked in a solution of 20% chloral hydrate and then mounted on a glass slide with the help of glycerine. The mounted slides were then observed under a photographic microscope. Microscopic sections were cut by free hand sectioning.Result: The research paper study revealed that the yellow colour inside the rhizome is the main characteristic feature. The presence of central cylinder region containing yellow coloured oleo-resin and oil cells in cortex are the main characteristic feature. The presence irregularly rounded, ovoid starch grains and oil globulues situtated inside the parenchyma are the distinguishing features and can be used as anatomical markers. Rhizome powder showed some of the characteristic features such as starch grains with a rounded shape situated at narrow end and parenchymatous cells with characteristically wrinkled wall, air spaces. Cork, cortex, cork cells, and floem fibres also shows pharmacognostical characteristics of Z. cassumunar Roxb. Preliminary phytochemical analysis of the rhizomes revealed the presence of glycosides, sterols, triterpenes, saponins, tannins, flavonoids, amino acids and volatile oils.Conclusion:The present study signifies the use of TLC (Thin layer chromatography) profiles for determining the identity of active chemical constituents.

Salinity attenuates nickel-accumulating capacity of Atropa belladonna L. plants

Comparative analysis of growth and composition of Atropa belladonna L. plants was performed after separate and combined additions of NaCl and NiCl2 to the nutrient medium. Plants were grown in water culture on modified Johnson solution for 8 weeks until the formation of the fifth leaf pair. Thereafter, NiCl2 was introduced at final concentrations of 100 and 150 μM into the medium either separately or in combination with 100 mM NaCl. After completing the 7-day treatment with Ni ions, the plants' weight and the content of water and photosynthetic pigments were determined. The content of Ni, free polyamines (putrescine, spermidine, spermine), and atropine was determined in plant roots and leaves, whereas the content of Fe, proline, and malondialdehyde (MDA) was examined in leaves only. The distribution of Ni in various tissues was inspected using the dimethylglyoxime method. The presence of NiCl2 in growth media diminished the increments in fresh weight of shoots and roots; lowered the content of water, pigments, and iron in leaves; and initiated chlorosis. The leaves of Ni-treated plants accumulated larger amounts of atropine, putrescine, proline, and MDA with respect to the control levels of these compounds. In contrast to the action of Ni alone, the combined application of NaCl and NiCl2 was followed by the increased content of water and pigments in leaves. The presence of NaCl in the medium restricted the entry of Ni into roots and diminished the levels of MDA and proline in leaves. After growing the plants in the presence of 100 and 150 μM NiCl2, nickel was located in the root outer cortex and the rhizoderm. In plants treated with 150 μM NiCl2, nickel was also observed in tissues of the central cylinder, mostly in the pericycle, phloem, and xylem. In plants grown in the presence of 150 μM NiCl2 and 100 mM NaCl, the decreased accumulation of nickel was noted in the tissues of the central cylinder in the root hair zone. Thus, the combined action of Ni and moderate salinity reduced nickel accumulation in roots and aboveground organs of A. belladonna plants. The reduced Ni content in plants mitigated the toxic effect of Ni present in the medium. This was manifested in stabilization of leaf water status, an increase in the content of photosynthetic pigments, and alleviation of oxidative stress, which was assessed from the content of low-molecular organic compounds exhibiting stress-protective and antioxidant action (proline, MDA, free polyamines, and atropine).

Bioprinted Osteogenic and Vasculogenic Patterns for Engineering 3D Bone Tissue.

Fabricating 3D large-scale bone tissue constructs with functional vasculature has been a particular challenge in engineering tissues suitable for repairing large bone defects. To address this challenge, an extrusion-based direct-writing bioprinting strategy is utilized to fabricate microstructured bone-like tissue constructs containing a perfusable vascular lumen. The bioprinted constructs are used as biomimetic in vitro matrices to co-culture human umbilical vein endothelial cells and bone marrow derived human mesenchymal stem cells in a naturally derived hydrogel. To form the perfusable blood vessel inside the bioprinted construct, a central cylinder with 5% gelatin methacryloyl (GelMA) hydrogel at low methacryloyl substitution (GelMALOW ) was printed. We also develop cell-laden cylinder elements made of GelMA hydrogel loaded with silicate nanoplatelets to induce osteogenesis, and synthesized hydrogel formulations with chemically conjugated vascular endothelial growth factor to promote vascular spreading. It was found that the engineered construct is able to support cell survival and proliferation during maturation in vitro. Additionally, the whole construct demonstrates high structural stability during the in vitro culture for 21 days. This method enables the local control of physical and chemical microniches and the establishment of gradients in the bioprinted constructs.

Relationship between mycorrhizal responsiveness and root traits in European sand dune species

Evolutionary detachment from mycorrhizal symbiosis and the resulting need for efficient autonomous nutrient acquisition may have induced a relationship between root architecture and mycorrhizal responsiveness in modern land plants. This study examines the predictability of mycorrhizal responsiveness from root architecture within the context of naturally co-occurring species from the same ecosystem type and age in an environment with the same nutrient, light and watering conditions. We attempted to relate 16 root morphological parameters with mycorrhizal responsiveness and mycorrhizal parameters in 13 species frequently co-occurring in European sand dune ecosystems. We found clear relationships of root architecture with mycorrhizal responsiveness, hyphal density and colonization level. All mycorrhizal parameters could be reliably predicted from a combination of root traits, involving ratio of cortex / central cylinder, root / shoot ratio and the number of forks per root length. This indicates the existence of the proposed relationship between root architecture and mycorrhizal responsiveness in the context of comparing differentially mycotrophic species from similar environments under similar conditions. However, surprisingly we did not find root architecture to be clearly adaptable towards AMF. Apparent changes in root architecture with mycorrhization in the studied species are thus rather to be evaluated as AMF effects on plant development, than as a direct adaptation of the root system to mycorrhizal foraging.

Structural features of Phalaris arundinacea in the Jianghan Floodplain of the Yangtze River, China

We examined reed canary grass, Phalaris arundinacea, under shallowly flooded conditions along the Jianghan Floodplain of the Yangtze River to determine structural traits with an emphasis on histochemistry of cell walls in endodermal, exodermal, and epidermal layers and to determine if these traits are consistent with those of other wetland plants of the Floodplain. Roots have an endodermis with Casparian bands, suberin lamellae, and secondarily lignified walls. Outside schizo-lysigenous aerenchyma of the cortex, a biseriate exodermis has Casparian bands and suberin lamellae and lignified walls, and often an internal suberized layer is present. Rhizomes have a thick cuticle, lignified peripheral mechanical ring with an exodermis, large cortical cavities, an endodermis delimiting a central cylinder and sclerenchyma ring, and pith cavities. Culms with leaf sheaths have a thick cuticle and an exodermis in a narrower peripheral mechanical ring, small cortical cavities, a central cylinder with a sclerenchyma ring and pith cavities, but no endodermis. Most vascular bundles are located in the central cylinder and its sclerenchyma ring. These structural features of reed canary grass are characteristic of plants adapted to the seasonal flooding of the Floodplain below the Three Gorges Reservoir Region of the Yangtze River in China.

Extinction and growth of cylindrical hotspots in AB model explosive: molecular dynamics studies

Atomistic simulations of a sample with AB model explosive heated quickly up within a small central cylinder were performed with the goal of finding a critical radius of such hotspot. The heating time was chosen to be much shorter than an acoustic time required for rarefaction wave for arriving to the center of hotspot. An isochoric thermal decomposition of AB material evolves inside the hotspot before the arrival of rarefaction wave. We found that the critical radius of such hotspots is determined by the equality of the acoustic time and a characteristic time of isochoric thermal decomposition controlled by initial hotspot temperature. For supercritical hotspots the decomposition of AB material leads to deflagration. The earlier arrival of rarefaction wave extinguishes the chemical reactions in hotspots with the subcritical radius.

Infestation of the banana root borer among different banana plant genotypes

ABSTRACT: In this study, we aimed to investigate Cosmopolites sordidus (Coleoptera: Dryophthoridae ) infestation among different banana genotypes in a commercial banana orchard over the course of 30 months. Banana root borer infestation was compared in 20 banana genotypes, including five varieties and 15 hybrids. Overall, we observed that 94.17% of pest infestation cases occurred in the cortex region, and only 5.83% occurred in the central cylinder. Genotypes least sensitive to infestation were the Prata Anã (AAB) and Pacovan (AAB) varieties, where no damage was recorded. Among the hybrid genotypes, PV 9401 and BRS Fhia 18 showed intermediate levels of sensitivity, while BRS Tropical hybrids (AAAB), PA 9401 (AAAB), BRS Vitoria (AAAB), YB 4203 (AAAB), and Bucaneiro (AAAA) were the most sensitive to attack by banana root borer. This study demonstrated that the infestation of the banana root borer varies according banana plant genotype, and the utilization of less susceptible genotypes could reduce infestation rates of C. sordidus.

Pharmacognostic,Pharmacognostic, Phytochemical and Antioxidant Studies of Hydnophytum formicarum L

The leaves of Hydnophytum formicarum Jack belonging to the family Rubiaceae, a tropical tree commonly found in eastern and southern Thailand, South Asia, Papua New Guinea and the Pacific Islands, were studied for these antioxidant compounds. Sterols, flavonoids and phenolic compounds appear to be good markers for this species. Chromatographic and histochemical techniques were used to analyze its secondary metabolites and to localize these molecules in the leaves of H. formicarum and its petiole. With histochemistry, we can locate the phenols in situ by an iron chloride reagent, which gives a black color, especially in fibers, hypodermis and xylem. Flavonoids are detected histochemically using a potassium hydroxide reagent to obtain a yellow coloration under visible light. Histochemical studies of H. formicarum showed a high concentration of natural antioxidants in the central cylinder, particularly in the vascular bundle, whereas condensed catechic tannins were mainly detected in collenchyma, fibers and also in xylem. The high levels of phenolic compounds and their localization in the conductive tissues allow us to explain the traditional medicinal use carried out in Thailand with this tree because, very often, compounds with antioxidant properties prove to be good anti-cancer agents.

Morphological-Anatomical Peculiarities of the Alhagi pseudalhagi L.

Morphological and anatomical descriptions of the Alhagi pseudalhagi L. have been given in the paper. Under the influence of environmental factors this plant acquired such structural features as the strong development of the central cylinder, strong omission, the presence of numerous and small conduction beams, thick cuticles, small and numerous stomata. These properties are typical for xerophytes.

<b>Flooding avoidance <i>Triplaris gardneriana</i> Wedd. (Polygonaceae): growth and morpho-anatomical aspects

The aim of this study was to analyze the effect of flooding in Triplaris gardneriana Wedd, cultivated in drained soil (control) and in flooded condition. The experiment was developed in a greenhouse, using plants with 90 days after the emergency. The response to treatment was evaluated at 0, 30, 60 and 90 days. Growth measurements were made, such as biomass allocation, relative growth rate (RGR). Adventitious roots were not measured only observed, as well as the development of hypertrophied lenticels. The RGR was continuously reduced along the 90 days in flooding conditions for the roots, stem and leaves, compared to control. The flooding of the substrate caused alterations such as: increasing of the cortex width and diameter of the central cylinder of root and increasing the diameter of the vessel element of the root and stem. Results show that T. gardneriana remains under stress when submitted to flooding. Therefore, the production of structures as lenticels, aerenchyma and adventitious roots, structures related to the avoidance of this type of stress, were key factors for the maintenance and survival of T. gardneriana.

Stimulation of metallic nanoparticles under the impact of radial magnetic field through eccentric cylinders: A useful application in biomedicine

This paper represents a new model of magnetohydrodynamic (MHD) peristaltic flow of nanofluid by considering the blood as the base fluid and copper and silver as the nanoparticles through eccentric annuli. An appropriate model of peristaltic pumping is introduced and it is encouraged due to the fact that thread infusion within the human body is a promising strategy for setting medical implants with least surgical trauma. The central cylinder is rigid and moving with consistent velocity V while the outlying tube has a sinusoidal wave going down through its wall. A magnetic field is imposed in radial direction to enhance the amplitude of wave (for synchronization avail in ECG). The complicated flow model equations are first simplified under the assumptions of long wavelength and low Reynolds number. Then series solutions are obtained for resulting system. The innovation with distinct sundry parameters are discussed via graphical illustrations. Comparison among the pure blood, silver blood and copper blood is presented and analyzed. It is also revealed that inclusion of nanoparticles enlarge the velocity of fluid.

Genetic and molecular mechanisms of post-embryonic root radial patterning

Arabidopsis root with its simple, consistent and well-defined pattern of cell division and growth is a highly tractable system for studying cellular development. The root apical meristem (RAM) of Arabidopsis, established post-embryonically is the main source of root cells. Complex bidirectional signaling between stem cells and mature root cells is required to maintain RAM activity. The Arabidopsis RAM comprises of a quiescent center (QC) and a niche of self-renewing stem cells that perform asymmetric (formative) cell divisions to generate daughter cells. These daughter cells subsequently divide symmetrically within delineated longitudinal cell files. The cells in the QC coordinate with neighboring stem cells to establish the balance between proliferation and differentiation in the meristem niche. The Arabidopsis primary root is composed of concentric rings of tissues (namely, the epidermis, the cortex, the endodermis and the pericycle, from the outside inwards) arranged in a radial axis that surrounds a central cylinder of vascular and procambial cells. Overlaid upon the radial organization of the root are three longitudinal zones viz, the meristem, the elongation zone and the differentiation zone, that describe cellular behavior. The boundaries of these domains are plastic and are largely regulated by antagonistic interactions between different phyto-hormones, which regulate the expression of key TFs. In this paper, we review the process of radial patterning in Arabidopsis thaliana post-embryonic root with an emphasis on genetic and molecular networks that determine the fate of each domain in the root.

Optimal design of the stacking sequences of a corrugated central cylinder in a satellite

This Case Study is to describe an application of a two-level approximation method in optimally determining the stacking sequences of a practical corrugated central cylinder. Being housed in the center of a practical satellite, this cylinder can support many of the structural components and functional devices in the satellite. For the purpose of reducing its mass meanwhile maintaining good mechanical properties, the stacking sequences of this cylinder are to be optimally designed under given constraints in this paper. To address this problem, an optimization model was first established by minimizing the structural mass based on initial lay-ups. With the given lay-ups for multi-parts of this cylinder, the existence of each ply was to be determined in terms of discrete variables. Meanwhile, the ply thicknesses were also treated as continuous variables. The two-level approximation method combined with a genetic algorithm previously proposed by the authors was adopted as the optimization method. According to the practical engineering considerations, multiple optimizations were conducted by starting from different initial lay-ups to search more possible optimization designs. After optimization, it was found that compared with the empirical designs, the mass of the main cylinder could be significantly decreased by obtaining some reasonable stacking sequences.

Metal storage in reeds from an acid mine drainage contaminated field

ABSTRACTPhragmites australis has been used to treat acid mine drainage (AMD)-contaminated soil. However, the mechanism about metal translocation in reeds was not widely reported. This study investigated metal (Fe, Al, and Mn) storage location in reeds grown in five different sampling sites of an AMD field. As expected, the more metals in soil, the more metals entered the belowground organs of plants. Reeds grown in soils with the highest levels of metals accumulated 0.16 ± 0.04 mg/g Mn, 16.29 ± 4.15 mg/g Fe, and 1.31 ± 0.22 mg/g Al in roots. Most of the iron was sequestered in the roots, while Al was transferred to the shoots. Histological staining found that most of the iron was sequestered in the exodermis, while Al extended the endodermis of roots. Al even entered the stele of roots grown in soil with higher Al levels. The epidermis, cortex, and central cylinder of rhizomes were the main tissues for Fe and Al storage. The more metals in rhizomes, the stronger intensity of the staining was observed around the vascular systems of rhizomes. No structural difference was observed among reeds collected from different sites. Further studies may be needed to enhance the transfer of metals in reeds and increase the phytoremediation efficiency.

Phytoremediation of petroleum hydrocarbons-contaminated soil using Desmodium incanum DC., Fabaceae

Abstract The current research aimed to investigate both the tolerance and the phytoremediation potential of Desmodium incanum DC. on petroleum-contaminated soil. There were analyzed D. incanum seeds germination, surviving, growth and development cultivated at different contaminants concentrations as well as the pollutant degradation rate by gas chromatography and rhizosphere community. The experiment was carried out on a greenhouse containing non-contaminated soil (NCS), vegetated contaminated soil (VCS) and non-vegetated contaminated soil (NVCS) at the following petroleum concentrations (petroleum per of dry soil): 50 g kg-1 and 100 g kg-1. The experiments were performed during 90 days. The germination was more evident as it was observed higher petroleum concentrations. After 90 days, the surviving rate of the both groups 100%, and the soil samples were extracted and analyzed by gas chromatography. The VCS (100 g kg-1) group growth was reduced when compared to the NVCS (100 g kg-1). The petroleum influenced the morph anatomy and development of the plant. Significant increases in the total area, cortical and central cylinder of the roots in the contamination presence. The plant provided the development of larger amounts of microorganisms in the rhizosphere zone, and higher petroleum compounds degradation, confirming their potential phytoremediation for soils contaminated by petroleum.