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Journal articles on the topic 'Stem section'
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1
Lee, Dong-Han, and Dongkyoo Kim. "A Plan for Applying Extended Reality to an English Textbook for Elementary School Students." STEM Journal 23, no. 3 (2022): 39–52. http://dx.doi.org/10.16875/stem.2022.23.3.39.
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The purpose of this study is to provide application plans for English textbooks for elementary school students through Extended Reality (XR). For this purpose, this study first investigated current trends and issues in the technology of XR including Virtual Reality (VR), Augmented Reality (AR), and Mixed Reality (MR). This study also investigated current studies of the application of XR technology in educational fields. Recent studies showed that applications of XR in English class for elementary school students were very rare. Only a few cases of applications of AR were found to be utilized for English class for elementary schools. Thus, this study suggested a direction of developing English education contents for elementary school students through the application of XR. A practical use of English textbook applied by XR is introduced on the basis of the contents of a textbook unit. Example sections of a class period in a textbook unit applied by XR were proposed. In each section, a developmental plan of class activities applied by XR was offered. In consideration of recent circumstances of technology, cost, and time, a developmental plan of class activities in each section applied was suggested in the order of VR, AR, and MR.
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Burcham, Daniel, Subhadip Ghosh, Leong Eng Choon, and Fong Yok King. "Evaluation of an Infrared Camera Technique for Detecting Mechanically Induced Internal Voids in Syzygium grande." Arboriculture & Urban Forestry 37, no. 3 (2011): 93–98. http://dx.doi.org/10.48044/jauf.2011.013.
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In order to evaluate a proposed tree diagnostic technique employing infrared cameras, research was conducted to evaluate the effect of internal voids on surface temperature using a thermal photographic instrument. Three axial cylindrical voids of increasing size (Void A, 327 cm3; Void B, 745 cm3; Void C, 1159 cm3) were introduced mechanically in 45 cm long stem sections and exposed to direct sunlight. Subsequently, infrared images were collected from two diametrically opposed sides of the stem sections at regular 30-minute intervals over 150 minutes. The collected images were evaluated visually to compare stem features with observed temperature anomalies, and temperature data was extracted from a vertical transect in the infrared images. The data extracted were compared against a control stem section without defects to determine the independent and combined effects of void size and internal position on surface temperature. Mean relative temperature revealed a significant temperature change in the stems containing mechanical voids compared to the control stem. Significant increases in mean relative temperature were recorded on the stems containing Void A and Void B compared to the control. However, there was no significant change in mean relative temperature on the stem section containing Void C.
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Small, Tanya, E. G. Rhoden, A. Woldeghebriel, and G. W. Carver. "KUDZU IN THE SOUTH: AN OLD ALTERNATIVE CROP." HortScience 26, no. 5 (1991): 498a—498. http://dx.doi.org/10.21273/hortsci.26.5.498a.
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Kudzu (Pueraria lobata) has become a pervasive weed in the southeast US. It has been receiving much attention recently and a study was initiated to evaluate the plant as an alternative food and feed source. Kudzu vines were sectioned into; 0-25, 25-50, 50-75 and 75-100 cm and analysed for acid detergent fiber (ADF), neutral detergent fiber (NDF), ash and crude protein content. Leaf ash content of kudzu increased while stem ash content decreased as the vine was sampled from the growing tip. Stem NDF increased from 44.4% at the 0-25 cm section to 57.83% at the 75-100 cm section of the vine, while leaf NDF declined from 52.23 to 39.01% for the same sections. The trend was reversed for ADF in the kudzu leaf and stem. Crude protein content of kudzu ranged from 18.45% at the 0-25 cm section for leaves to 7.42% for stem sections at 75-100 cm. The high crude protein content of kudzu as well as its abundance in the Southeast makes it a good feed source and a potential food source. However, further studies are needed to determine the vitamin content and digestion coefficient to ascertain its suitability as a food and feed source.
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Guedes, N. M. P., and P. H. Jennings. "Somatic Embryogenesis Using Cucumis sativus (L.) Cotyledons." HortScience 31, no. 4 (1996): 630c—630. http://dx.doi.org/10.21273/hortsci.31.4.630c.
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To improve somatic embryogenesis of Cucumis sativus, two types of explants (cotyledons and stem sections) were cultured on Murashige and Skoog (MS) media supplemented with 2,4-D (2.0 mg·L–1) + kinetin (0.5 mg·L–1). After 4 weeks, the embryogenic callus was transferred for 2 weeks to MS + NAA (1.0 mg·L–1) for embryo development. Stem sections failed to develop embryos while cotyledons responded with 14% embryo formation. The embryos were transferred to MS without hormones for 4 weeks to allow for plantlet growth. These embryos developed only shoots. To improve on the successful generation of embryos with root and shoot development, the procedures used above were repeated, but the cotyledons were cut into three sections to be used as explants. Each transverse section of the cotyledon was approximately 2–3 mm wide. All sections produced callus but not all of them were embryogenic. From the first section (cotyledon base), the second (between the first and third section) and the third section (furthest from the cotyledon base), respectively, 58%, 31%, and 5% embryo development occurred. Those embryos from the basal cotyledon sections regenerated 10 plantlets, 5 with shoots and roots and 5 with only shoots. Approaches to enhance somatic embryogenesis, and shoot and root development, will be discussed.
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Henry, Paul H., and John E. Preece. "Production of Shoots from Dormant Species of Acer as Influenced by Length and Caliper of Stem Sections." Journal of Environmental Horticulture 15, no. 3 (1997): 153–56. http://dx.doi.org/10.24266/0738-2898-15.3.153.
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Abstract Stem sections removed from selected, dormant species of Acer L. (maples) were forced to produce softwood shoots under greenhouse conditions. Species and clones varied widely in the percentage of stem sections forming shoots, and in the number of shoots that were generated per section. Both length and diameter of sections influenced the number of shoots that were generated. With respect to length, it was best to use stem sections of 30 to 40 cm (11.8 to 15.7 in) since longer sections failed to produce additional shoots and occupied considerably more production space. Effect of increased stem diameter varied across species. For A. rubrum, the number of shoots produced was greatest on ‘large’ diameter (5.2 to 7.6 cm; 2.0 to 3.0 in) stem sections; shoot production was greatest on ‘medium’ diameter (3.3 to 5.1 cm; 1.3 to 2.0 in) stem sections of A. palmatum. Data indicate that an optimum diameter will have to be determined for each species that is propagated when using this method.
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Valleser, V. C. "Exogenous application of gibberellic acid on lateral bud emergence in pineapple propagated through stem cuttings." Food Research 7, no. 5 (2023): 297–301. http://dx.doi.org/10.26656/fr.2017.7(5).010.
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The effects of gibberellic acid (GA3) on lateral bud emergence in pineapple stem is still not known. Hence, this study was conducted. ‘MD2’ pineapple stems were sectioned into vertical halves. The first half served as the control (untreated). Whereas the other halves were soaked in 500 ppm GA3 for 2 hrs. The study was performed in two trials. Results in both trials show that untreated stem sections produced lateral buds after one week. In contrast, the GA3 treatment prevented the development of buds. In trial 1, only 2 out of 18 stem sections (11.11%) soaked in 500 ppm of GA3 produced buds after one week. In trial 2, GA3-treated stem sections failed to produce buds. The average number of buds emergence per stem section and diameter of lateral buds were consistently better in untreated pineapple stem sections. These findings implied that the exogenous application of GA3 could prevent the emergence of lateral buds in the pineapple stem.
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Schatten, Heide. "Introduction to Stem Cell Special Section." Microscopy and Microanalysis 17, no. 4 (2011): 473. http://dx.doi.org/10.1017/s1431927611011998.
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The prospect of utilizing stem cells for clinical applications has generated an enormous amount of enthusiasm in the stem cell research community and has led to a wealth of new data that offer the possibility for practical applications into clinical translation. Recent advances in stem cell imaging has contributed greatly to the ultimate goal to identify and culture specific cell types for regeneration of tissue that had been affected by disease such as Parkinson's, Alzheimer's, heart disease, muscle diseases, and others.
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Dwinanda, Aldi Rivaldi, Bambang Setia Nugroho, and Aloysius Adya Pramudita. "Modeling of Cavities Detection in The Tree Stemsection Using Radar Vector Network Analyzer (VNA) Elaborating Radon Transform." Journal of Measurements, Electronics, Communications, and Systems 9, no. 1 (2022): 29. http://dx.doi.org/10.25124/jmecs.v9i1.5370.
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Trees are one of the most useful plants for life on earth. However, trees can be harmful due to cavities in the stem sections. Rapid detection is needed to prevent several losses that may arise due to fallen trees. This research identified a hollow and non-hollow tree stem section of flamboyant tree with a sub-surface detection radar system. The sub surface detection radar system was modeled using a Vector Network Analyzer (VNA) connected to a Vivaldi antenna. VNA emitted electromagnetic waves to the tree stem section and subsequently propagated and penetrated hollow tree stem section. The propagation wave met the boundary plane between the wood and the cavity which reflected the electromagnetic waves. The reflected wave was caught by antenna and was display by the VNA as S-Parameter. This research used a Vivaldi antenna with a working frequency of 1 GHz – 10 GHz and a VNA with working frequency 300KHz - 8GHz. The difference in the amplitude of the signal could be seen from the results of cavity measurements made at one point. By implementing circular scanning method with inverse radon transformation, this research could identify a 19 cm diameter wood with a hole of 6 cm and 9.5 cm diameter filled with water, respectively. It was observed that the optimal detection was obtained by placing object between the antennas. This research has signified the application of radar modeled with VNA for detecting the cavities in tree stem section.
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Canne-Hilliker, Judith M., and Christine M. Kampny. "Taxonomic significance of leaf and stem anatomy of Agalinis (Scrophulariaceae) from the U.S.A. and Canada." Canadian Journal of Botany 69, no. 9 (1991): 1935–50. http://dx.doi.org/10.1139/b91-243.
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Features of foliar and stem anatomy of 26 annual and 1 perennial species of North American Agalinis were examined from over 200 population samples. Several species including A. aphylla, A. densiflora, A. filicaulis, A. heterophylla, A. linifolia, A. maritima, and A. oligophylla have distinctive anatomy. Evidence from anatomy supports a reclassification of North American Agalinis at the sectional and subsectional ranks. Agalinis aphylla and A. oligophylla are allied with species of section Erectae, not section Purpureae subsection Setaceae. Agalinis edwardsiana (from section Tenuifoliae) and A. aspera (section Asperae) are most similar to members of section Purpureae subsection Pedunculares. Agalinis tenuifolia (section Tenuifoliae) is similar to species of section Purpureae subsection Purpureae. Anatomical characters range from those usually regarded as xeromorphic to those typical of hydromorphic species. However, different xeromorphic characters are present in species of sections Purpureae, Erectae, and Tenuifoliae. Species of section Purpureae subsection Setaceae have filiform, adaxially grooved leaves; species of section Erectae have narrow, short sclerenchyma-reinforced leaves and very slender stems usually having fiber bundles in their ridges. Species that we retain in section Tenuifoliae have a cylinder of sclerenchyma between the vascular tissues and the fiber-laden cortex. Key words: Agalinis, Scrophulariaceae, anatomy, systematics, taxonomy.
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Pleasants, Kathleen. "Integrative Approaches in Education: Bridging STEM and the Arts." Xpertno International Journal of Interdisciplinary Research 1, no. 1 (2023): 30–42. https://doi.org/10.5281/zenodo.10053569.
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This research embarked on a meticulous exploration of integrative approaches in education, with a predominant focus on the confluence of Science, Technology, Engineering, Arts, and Mathematics (STEAM). The study was woven into a rich tapestry of interdisciplinary inquiry, aiming to unveil the multifaceted dimensions and impacts of STEAM education through a symphony of quantitative and qualitative methodologies. Surveys and interviews paved the path of investigation, leading to a confluence of findings that illuminated the landscape of STEAM with nuanced insights into participant experiences, perceptions, and pedagogical implications. Key findings revealed STEAM education as a vibrant catalyst fostering creativity, engagement, and an inclusive learning environment. However, challenges echoing with the nuances of authentic integration and implementation intricacies also reverberated within the narrative of results. The discussion section traversed through interpretative pathways, connecting empirical evidence with theoretical paradigms, and elucidating recommendations that resonate with future trajectories of research and practice in the vibrant realms of STEAM education.
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Packa, Danuta, Marian Wiwart, Elżbieta Suchowilska, and Teresa Bieńkowska. "Morpho-anatomical traits of two lowest internodes related to lodging resistance in selected genotypes of Triticum." International Agrophysics 29, no. 4 (2015): 475–83. http://dx.doi.org/10.1515/intag-2015-0053.
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Abstract The cross-sections of first and second internodes were analyzed under a light and fluorescence microscopes in six varieties of Triticum spelta, two varieties of T. polonicum, and one variety of T. aestivum. The morphometric parameters of stem cross-sections were measured. The analyzed wheats were characterized by significant differences in traits associated with lodging resistance ie: internode diameter, lumen diameter, stem wall thickness, mechanical layer thickness, area of transverse section, and area of lumen for the first and second internode and between the internodes. In all varieties, the values of internode diameter, lumen diameter, area of transverse section and area of lumen were higher for the second internode than for the first internode, whereas the reverse was reported for stem wall thickness and mechanical layer thickness The results of the principal component analysis and section modulus values revealed similarities between spring spelt Wirtas and Rubinas and between common wheat Kontesa and winter spelt Poeme and Epanis. The number of large vascular bundles varied across the studied varieties. The average number of vascular bundles in common wheat Kontesa was significantly higher than in spring spelt Rubinas and Wirtas and significantly lower than in Polish wheat Pol-3 and winter spelt Epanis and Poeme.
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Hafsa Qabool, Jaweriya Qabool, Aqeel Ahmed, Rashna Hoshang Sukhia, and Mubassar Fida. "Knowledge and awareness of dental stem cells among dental healthcare professionals – a cross-sectional study." Journal of the Pakistan Medical Association 73, no. 2 (2023): S9—S13. http://dx.doi.org/10.47391/jpma.akus-02.
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Objective: To assess knowledge and awareness of dental healthcare professionals on dental stem cells. Methods: A questionnaire survey-based study was conducted using Google forms on a sample of 69 dental healthcare professionals (DHCP) from September – October 2022, after obtaining ethical approval. A validated questionnaire was used to assess the knowledge and awareness of dental healthcare professionals on stem cells, which was then divided into three sections. The section A was about demographic statistics, section B assessed knowledge and awareness regarding dental stem cells and section C consisted of 5 score VAS scale to assess the acceptability of future research and increase implication of dental stem cells (DSC) among DHCP. The frequency of each question was reported in percentages. To assess the difference of knowledge and awareness of DSC among different specialties of DHCP, one-way ANOVA test was applied and incase of significant results pairwise comparison was performed by post-hoc Tukey test. Results: Mean scores of knowledge and awareness of DSC among female DHCP were 54.26 ± 11.73 and males were 53.50 ±8.19. There was a statistically significant difference of knowledge (p= 0.02) among different dental healthcare professionals. On pairwise comparison by post-hoc Tukey HSD we found statistically significant difference (p = 0.03) of knowledge and awareness of dental stem cells among general dentists and operative dentistry specialists. Conclusion: We found poor knowledge and awareness of dental healthcare professionals regarding dental stem cells. However, operative and endodontic specialty had more awareness on dental stem cells as compared to any other specialty. There was positive approach for further future researches on stem cells. Keywords: Dentistry, Operative, Stem Cells, Demography.
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Wang, Qingshuang, Jingjie Ban, Roudi Cai, et al. "Metabolic Composition and Quality Traits of Polygonatum cyrtonema Hua from Different Germplasms and Age Sections Based on Widely Targeted Metabolomics Analysis." International Journal of Molecular Sciences 24, no. 7 (2023): 6077. http://dx.doi.org/10.3390/ijms24076077.
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Polygonatum rhizomes are rich in various compounds with many biological activities and are widely used in functional foods and pharmaceutical products. In order to screen for superior Polygonatum cyrtonema Hua (P. cyrtonema) germplasm and also to elucidate the nutritional and medicinal values of rhizomes, the metabolic composition and quality traits of rhizomes from different germplasms and age sections of P. cyrtonema were analysed by widely targeted metabolomics, and the molecular mechanism of triacylglycerol synthesis was explored. The results showed that the different germplasms and age sections of P. cyrtonema were rich in different nutritional and medicinal components. Of these, the broad-leaved green stem (GK) germplasm is rich in polysaccharides, alkaloids, and lipids; the pointed-leaved green stem (JL) germplasm is rich in flavonoids, steroids, and amino acids, while the pointed-leaved purple stem (JZ) germplasm contains more phenolic acids. The one-year (AT) age section is rich in polysaccharides, steroids, organic acids, and lipids; the three years (CT) age section contains more flavonoids, alkaloids, and amino acid metabolites. Lipids were significantly enriched in the broad-leaved green stem germplasm and the one-year age section. Interestingly, the highest accumulation of triacylglycerols, an important component of lipids, was also found in the GK germplasm and the AT age section. Nineteen, 14, and 13 members of the glycerol-3-phosphate acyltransferase (GPAT), lysophosphatidic acid acyltransferase (LPAT), and diacylglycerol acyltransferase (DGAT) gene families, respectively, involved in triacylglycerol synthesis were also identified. The quantitative real-time PCR (qRT-PCR) results further suggested that the differentially expressed PcDGAT1, PcDGAT2.4, PcGPAT9.1, PcLPAT2.9, and PcLPAT4.3 genes may play important roles in triacylglycerol synthesis in P. cyrtonema. Therefore, this study provides a new theoretical reference for product development and the breeding of new varieties of Polygonatum species.
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Quesenberry, Peter. "Stem Cell Reviews and Reports: Cancer Stem Cells and Aging Section." Stem Cell Reviews and Reports 13, no. 1 (2017): 6. http://dx.doi.org/10.1007/s12015-017-9727-3.
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Berezkina, V. "The peculiarities of the morpho-anatomical structure of the vegetative organs of Sedum L. species (Crassulaceae DC.)." Modern Phytomorphology 2 (April 1, 2012): 157–59. https://doi.org/10.5281/zenodo.162632.
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The results of study of the morpho-anatomical structure of the vegetative organs of two species of the genus Sedum L. (Crassulaceae DC.): S. telephium L. – representative of the section Telephiastrum S.F. Gray. and S. rubrotinctum R.T. Clausen – representative of the section Pachysedum Bgr. from collection of Fomin Botanical garden have been presented. On the basis of comparison of the morpho-anatomical features of investigated species the general signs of anatomical structure of representatives from different sections of the genus Sedum have been set.
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Adenegan-Alakinde, T. A., and F. M. Ojo. "Stem anatomical studies of two species of <i>Talinum</i> occurring in Southwest, Nigeria." Ife Journal of Science 27, no. 1 (2025): 61–71. https://doi.org/10.4314/ijs.v27i1.6.
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Taxonomic relationship using anatomical features of the stems ofTalinum triangulare (Jacq.) Willd and Talinum paniculatum(Jacq.) Gaertn. was investigated. Transverse Section, Tangential Longitudinal Section (TLS), and Radial Longitudinal Section (RLS) of mature stems of each of the species were cut at 8 - 15 µm with the aid of a Reichert sliding microtome. Stem cuttings of about 10 cm of each species were also macerated using 10% Sodium hydroxide solution. Sections and macerates were stored in 50% ethanol. Sections and macerates were stained and viewed under the microscope. The study showed that the species had similar stem anatomical features, indicating close affinity and being members of the same genus but could still be separated based onthe presence of brachysclereid, osteosclereid, and multiseriate rays randomly distributed in T. triangulare while T. paniculatum has more regularly arranged multiseriate rays with neither brachysclereids nor osteosclereids. The compound rays of T. paniculatum are thin walled but thick-walled in T. triangulare. The ray cells in T. triangulare are more or less similar, but in T. paniculatum, the ray cells reduce in size from the peripheral region to the centre.
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Haywood, James D. "Influence of Precommercial Thinning and Fertilization on Total Stem Volume and Lower Stem Form of Loblolly Pine." Southern Journal of Applied Forestry 29, no. 4 (2005): 215–20. http://dx.doi.org/10.1093/sjaf/29.4.215.
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Abstract Two cultural treatments were applied in an overstocked loblolly pine (Pinus taeda L.)plantation (2,900 trees/ha after eight growing seasons): precommercial thinning (Yes or No) to 747 trees/ha after the eighth growing season and broadcast fertilization (Yes or No) with diammonium phosphate (150 kg/ha of P and 135 kg/ha of N) early in the ninth growing season. Total height and diameter at breast height (dbh) measurements were taken periodically through the 14th growing season. Fertilization increased tree volume more than thinning in the 9th through 10th growing seasons, but thinning was most effective by the 13th growing season. Over the 6-year period, thinning was the most effective cultural practice: check, 110 dm3; fertilized only, 135 dm3; thinned only, 165 dm3; and thinned and fertilized, 220 dm3/loblolly pine tree. After the 14th growing season, the first 5 m of bole was divided into five sections beginning at a 15-cm stump height: 15–30, 30–60, 60–125, 125–250, and 250–500 cm, and the volume for each section was calculated. Outside-bark volume per section increased consistently with thinning and fertilization; therefore, cultural practices did not change stem form in the lower bole. South. J. Appl. For. 29(4):215–220.
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Ulrich, Henning. "Stem Cell Reviews and Reports: Induced Pluripotent Stem Cells, Embryonic Stem Cells and Development Section." Stem Cell Reviews and Reports 13, no. 1 (2017): 3. http://dx.doi.org/10.1007/s12015-017-9722-8.
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Pritchard, M. K., and M. G. Scanlon. "Mapping dry matter and sugars in potato tubers for prediction of whole tuber process quality." Canadian Journal of Plant Science 77, no. 3 (1997): 461–67. http://dx.doi.org/10.4141/p96-111.
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Processing quality parameters within different sections of potato (Solanum tuberosum L.) tubers grown in Manitoba were measured to determine variability within tubers and to determine if whole tuber quality could be predicted from a specific section. The section that provided the best prediction of overall tuber quality parameters was determined. Changes in specific gravity (SG) and sugars in the outside and the inside of tubers during several months of storage were also measured. Dry matter (DM) of potato cvs. Russet Burbank and Shepody was generally higher at the apical and stem ends than in the middle section and was significantly higher in the outside than in the inside of the tuber. Sucrose concentration generally decreased from the stem end to the apical end of the tuber in Russet Burbank but increased from the stem end to the apical end in Shepody. Sucrose, glucose, and fructose were generally greater, though not always significantly, in the inside of the tuber compared with the outside with the exception of sucrose in Shepody where it was somewhat higher in the outside section. Glucose and fructose generally decreased from stem end to apical end although the difference between the two ends was significant only in Shepody. There was more variability in DM and the three sugars within Shepody tubers than those of Russet Burbank. The outer section of the tuber at the centre of the longitudinal axis (CO) was, overall, most highly correlated to the DM (r2 > 0.91) of the entire tuber for both cultivars and would be the most appropriate single location for estimating the DM of the entire tuber. Sugar concentrations of whole tubers could not consistently be estimated from that of any particular tuber location although the CO section had the highest correlations overall. During 6 mo storage SG did not change while sucrose decreased and glucose and fructose generally increased in both the outside (CO) and inside (CI) of the tuber. Linear regressions relating DM, SG, and sugars of the CO section to the whole tuber, and relating DM to SG were developed. Key words: Solanum tuberosum L., specific gravity, storage, processing, product quality
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Eto, S., H. Masuda, Y. Hiraoka, M. Matsushita, and M. Takahashi. "PRECISE CALCULATION OF CROSS SECTIONS AND VOLUME FOR TREE STEM USING POINT CLOUDS." ISPRS - International Archives of the Photogrammetry, Remote Sensing and Spatial Information Sciences XLIII-B2-2020 (August 12, 2020): 205–10. http://dx.doi.org/10.5194/isprs-archives-xliii-b2-2020-205-2020.
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Abstract. Woody biomass is an important parameter in forestry and forest research. In order to estimate of woody biomass, it is important to precisely and efficiently calculate section areas and volumes of tree stems in the forest. In this paper, we propose a method for calculating the cross-sectional area and the stem volume of trees from point clouds captured using the terrestrial laser scanner. In our method, each point cloud is converted into a wireframe model, and cross-section points are calculated as intersection between the wireframe and the horizontal planes placed at equal intervals. Cross-sectional shapes on each horizontal plane are approximated as n-sided polygons and refined using the subdivision scheme. The section areas and stem volumes are calculated using the subdivision curves of stem contours. In our evaluation, our method could calculate section areas and stem volumes of trees with sufficient accuracy in practical use.
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H. AL-Hadeethi, Muazaz Azeez, Lanja hewa Khal, and Jwad Kadhem Ali. "Anatomical features of Fraxinus ornus L. growing in Iraq." Ibn AL- Haitham Journal For Pure and Applied Sciences 33, no. 3 (2020): 11. http://dx.doi.org/10.30526/33.3.2468.
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Fraxinus ornus L. is considered as a special species that is frequently planted as a decorative tree in most of the country. The cross-sections of the root and stem are circular in shape and in the secondary growth stage, the vascular tissue in the root and stem consists of secondary xylem in radial rows and the type of vessels in the xylem are ring pours wood. Epidermal cells of leaves undulate on the upper and lower side, hairs are uniseriate and unicellular and the stomata appeared in the abaxial surface only is anomocytic type. The vertical-section of blade leaf includes upper epidermis and lower epidermis followed by the palisade layer and spongy layers. The cross-section of petiole horseshoe shape and the vascular bundles are covered by sclerenchyma cells and distributed as groups.
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Wilson, JR, KL Anderson, and JB Hacker. "Dry matter digestibility in vitro of leaf and stem of buffel grass (Cenchrus ciliaris) and related species and its relation to plant morphology and anatomy." Australian Journal of Agricultural Research 40, no. 2 (1989): 281. http://dx.doi.org/10.1071/ar9890281.
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Twenty-one genotypes of buffel grass (Cenchrus ciliaris), and six other genotypes, viz. C. setigerus, C. Pennisetiforrnis and C. ciliaris x C. setigerus hybrids, were examined for dry matter digestibility in vitro (DMD) of recently expanded leaf and stem at anthesis. Differences in DMD were related to morphological and anatomical characteristics of the tissues.Leaf DMD ranged from 64.0 to 73.4%0 and stem DMD (internodes 2-4 from the top) from 47.4 to 61.7%; genotypes of high leaf DMD generally had high stem DMD (r= 0.68). Leaf DMD was negatively correlated with the proportion of thick-walled tissues in leaf cross-section (r= -0.76), leaf dry weight (r= 0.77 ) and specific leaf weight (r= -0.82). Stem DMD was inversely related to the proportion of lignified tissue in stem cross-section (r= -0.55), height of flowering stem (r= -0.51) and total number of vascular bundles in the stem section (r= -0.55). Genotypes with a high DMD tended to have lax leaves and small vegetative tillers.The main commercial cultivars of buffel, viz. American, Biloela and Gayndah, were 4-6% units (leaf) and 2.5-7% units (stem) lower in DMD than the best genotype, indicating potential for improvement of digestibility. Specific leaf weight and numbers of vascular bundles in stem cross-section, which arc easily and quickly measured and have a heritability comparable to that for DMD, could be useful criteria for preliminary assessment of a large breeding population.
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Cottler-Fox, Michele H., Tsvee Lapidot, Isabelle Petit, et al. "Stem Cell Mobilization." Hematology 2003, no. 1 (2003): 419–37. http://dx.doi.org/10.1182/asheducation-2003.1.419.
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Abstract Successful blood and marrow transplant (BMT), both autologous and allogeneic, requires the infusion of a sufficient number of hematopoietic progenitor/stem cells (HPCs) capable of homing to the marrow cavity and regenerating a full array of hematopoietic cell lineages in a timely fashion. At present, the most commonly used surrogate marker for HPCs is the cell surface marker CD34, identified in the clinical laboratory by flow cytometry. Clinical studies have shown that infusion of at least 2 × 106 CD34+ cells/kg recipient body weight results in reliable engraftment as measured by recovery of adequate neutrophil and platelet counts approximately 14 days after transplant. Recruitment of HPCs from the marrow into the blood is termed mobilization, or, more commonly, stem cell mobilization. In Section I, Dr. Tsvee Lapidot and colleagues review the wide range of factors influencing stem cell mobilization. Our current understanding focuses on chemokines, proteolytic enzymes, adhesion molecules, cytokines and stromal cell-stem cell interactions. On the basis of this understanding, new approaches to mobilization have been designed and are now starting to undergo clinical testing. In Section II, Dr. Michele Cottler-Fox describes factors predicting the ability to mobilize the older patient with myeloma. In addition, clinical approaches to improving collection by individualizing the timing of apheresis and adjusting the volume of blood processed to achieve a desired product are discussed. Key to this process is the daily enumeration of blood CD34+ cells. Newer methods of enumerating and mobilizing autologous blood HPCs are discussed. In Section III, Dr. John DiPersio and colleagues provide data on clinical results of mobilizing allogeneic donors with G-CSF, GM-CSF and the combination of both as relates to the number and type of cells collected by apheresis. Newer methods of stem cell mobilization as well as the relationship of graft composition on immune reconstitution and GVHD are discussed.
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Koizumi, Akio, and Takuro Hirai. "Evaluation of the section modulus for tree-stem cross sections of irregular shape." Journal of Wood Science 52, no. 3 (2006): 213–19. http://dx.doi.org/10.1007/s10086-005-0747-2.
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Zakrzewski, W. T. "A Mathematically Tractable Stem Profile Model for Jack Pine in Ontario." Northern Journal of Applied Forestry 16, no. 3 (1999): 138–43. http://dx.doi.org/10.1093/njaf/16.3.138.
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Abstract A new model was derived to describe the inside bark cross-sectional area of tree stems. It is a rational function. The inputs required by the model are outside bark tree diameter at breast height (DBH) and total tree height (H). Knowledge of a species-specific bark thickness at 1.3 m expressed in terms of input variables is also needed. Defining the model involves estimating two regression coefficients using either nonlinear or linear regression (after linearization of the model). The formula is analytically integrable and thus provides analytical inside bark volume estimates for any stem section defined by height limits. The model is analytically solvable for a stem height location at any given inside bark diameter, so that stem sections can be defined by the required inside bark diameter limits. The new model can be calibrated using either section diameter or section volume data. It is suggested that involving the ratio H/DBH in the model accounts for the influence of stand density on stem profile. The formula was calibrated for jack pine (Pinus banksiana Lamb.) in Ontario. Wider applicability of the model is supported by results obtained for sugar maple (Acer saccharum Marsh.) in Ontario and Scots pine (Pinus silvestris L.) in Finland. Comparing volume estimates from the new model with those generated by Honer's formula confirms the advantages of the new model. North. J. Appl. For. 16(3):138-143.
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Md., Mahabubur Rahman, and Sharmin Sultana Rubaiyat. "Stem, Leaf and Root Anatomy of Eclipta alba (L.) Hassk. (Asteraceae)." EBAUB Journal 1 (January 1, 2019): 1–7. https://doi.org/10.5281/zenodo.6507983.
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Anatomical studies on transverse sections of stem, leaf and root were conducted under light microscope to find out identical characteristics of <em>Eclipta alba</em> (L.) Hassk, belongs to the Asteraceae family. Free hand transverse sections stained with safranin were studied here. In stem section, epidermis, hypodermis, endodermis, vascular bundle and pith characters were general without cortex. A number of air cavities setup scatteredly in cortex, where seen secretory structures closed to air cavities. Average diameters determined 34, 62, 20 and 92 µm in cortex, air cavity, metaxylem and pith cells, respectively. Amphistomatic leaf sections presented a relatively thick cuticle layer on the adaxial surface. Anisocytic stomata (19 ± 0.1 µm in diameter) at a large quantity in the abaxial surface, counted 4 stomata per µm<sup>2</sup>. The mesophyll was dorsiventral, composed of one layer palisade and four layers spongy parenchyma. The vascular system in leaf was open, collateral conjoint forming a flattened arch in the triangular shape. Secretory structure as single or group located laterally in the cortical parenchyma of leaf sections. At leaf blade side, upper epidermis, spongy and palisade cells showed 37, 33 and 74 µm diameter, respectively. Upper epidermis, cortex and metaxylem cells diameter at midrib were 12, 38 and 14 µm, respectively. In root section, the cortical zone (cortex cell 49 µm) was wide and a large region occupied with air cavities (72 µm) although other parts like epidermis (32 µm), endodermis and vascular bundle (metaxylem 23 µm) characteristics were standard. The thick cuticle on the adaxial surface of leaf is a special feature for the plant studied. The presence of air cavity in stems and roots suggested to adaptability in aquatic condition. The secretory structure in stems and leaves can be an identical character for the experimental plant as well as Asteraceae family.
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Scott, Edward W. "Stem Cell Reviews and Reports: Adult Stem Cells and Tissue Regeneration Section." Stem Cell Reviews and Reports 13, no. 1 (2017): 2. http://dx.doi.org/10.1007/s12015-017-9724-6.
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Dr., Md. Mahabubur Rahman, and Sharmin Sultana Rubaiyat. "Anatomy and Developmental Changes in Stem of Leucas aspera (Wild.) Link. (Lamiaceae)." EBAUB Journal 1 (January 1, 2020): 1–8. https://doi.org/10.5281/zenodo.6506311.
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Anatomical studies on transverse sections of stem, leaf and root were conducted under light microscope to find out identical characteristics of <em>Eclipta alba</em> (L.) Hassk, belongs to the Asteraceae family. Free hand transverse sections stained with safranin were studied here. In stem section, epidermis, hypodermis, endodermis, vascular bundle and pith characters were general without cortex. A number of air cavities setup scatteredly in cortex, where seen secretory structures closed to air cavities. Average diameters determined 34, 62, 20 and 92 µm in cortex, air cavity, metaxylem and pith cells, respectively. Amphistomatic leaf sections presented a relatively thick cuticle layer on the adaxial surface. Anisocytic stomata (19 ± 0.1 µm in diameter) at a large quantity in the abaxial surface, counted 4 stomata per µm<sup>2</sup>. The mesophyll was dorsiventral, composed of one layer palisade and four layers spongy parenchyma. The vascular system in leaf was open, collateral conjoint forming a flattened arch in the triangular shape. Secretory structure as single or group located laterally in the cortical parenchyma of leaf sections. At leaf blade side, upper epidermis, spongy and palisade cells showed 37, 33 and 74 µm diameter, respectively. Upper epidermis, cortex and metaxylem cells diameter at midrib were 12, 38 and 14 µm, respectively. In root section, the cortical zone (cortex cell 49 µm) was wide and a large region occupied with air cavities (72 µm) although other parts like epidermis (32 µm), endodermis and vascular bundle (metaxylem 23 µm) characteristics were standard. The thick cuticle on the adaxial surface of leaf is a special feature for the plant studied. The presence of air cavity in stems and roots suggested to adaptability in aquatic condition. The secretory structure in stems and leaves can be an identical character for the experimental plant as well as Asteraceae family.
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Newton, Peter F. "Examining Naturogenic Processes and Anthropogenic Influences on Tree Growth and Development via Stem Analysis: Data Processing and Computational Analytics." Forests 10, no. 12 (2019): 1058. http://dx.doi.org/10.3390/f10121058.
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The objective of this study was to develop a stem analysis data processing and computational algorithm and associated software suite that was (1) applicable to temperate and boreal forest tree species, (2) mathematically consistent with excurrent tree stem geometric and allometric principles, (3) compatible with data structures obtained using proprietary and non-proprietary imaging systems, and (4) executable on Windows®-based operating systems. Computationally, the suite denoted SAP (Stem Analysis Program), deployed sectional-specific formulae that were in accord with the following geometric assumptions: (1) stump section was treated as a solid of revolution resembling a cylinder; (2) sections between the stump and the tip were treated as a solid of revolution resembling a frustum of a cone for sections with continuous annual increments, otherwise treated as a cone; and (3) tip section was treated as a solid of revolution resembling a cone. The algorithm also corrected for the slant-based sectional length measurements using Pythagorean Theorem and eliminated the requirement to predict age-specific apex height development through the use of a linear interpolation procedure. Based on input data structures consisting of annual ring-width xylem sequences measured from cross-sectional disk samples acquired at multiple positions along the tree’s main stem, the suite produces a broad array of output, inclusive of radial and longitudinal ring-width sequences, apical growth increments, annual and cumulative sectional and cumulative volume production patterns, and historically reconstructed stem taper profiles. In total, the SAP creates six output data files for each tree analyzed: (1) input data reference summary (e.g., geometric mean ring-widths and resultant radii for each cross-section); (2) radial growth patterns for the cross-section sampled at breast-height (e.g., absolute and relative diameter and basal area growth estimates); (3) sectional (vertical) profiles of volume growth patterns (e.g., absolute and relative growth estimates within each section (bolt)); (4) cumulative volume growth patterns for the entire tree; (5) historical taper profile estimates (e.g., heights and diameters by year); and (6) texturally-labeled compendium of all output files generated. Additionally, real-time graphical output was produced for the purposes of data assessment and verification during the radial sequence data acquisition stage (e.g., graphical presentation of annual ring-width sequences by radii and disk, for use in validating input data structures and increment measurements derived from the imaging system), and interpreting growth and development patterns (e.g., vertical growth layer and specific volume increment profiles by age or year). The utility of the SAP suite was exemplified by processing WindendroTM-based annual ring-width xylem sequences obtained from cross-sectional disks extracted from a jack pine (Pinus banksiana Lamb.) tree via percent-height destructive stem analysis, and subsequently elucidating growth and developmental patterns within the context of silviculture treatment effects (thinning). The SAP suite provides the conceptual and logistical foundation for the continued deployment of the stem analysis approach in a wide range of investigations, including those examining the effect of naturogenic processes and anthropogenic influences on tree growth and development.
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Sato, Takahiro, Yuya Suzuki, Hiroyuki Ito, Toshiyuki Isshiki, and Kuniyasu Nakamura. "Three Dimensional Dislocation Analysis of Threading Mixed Dislocation Using Multi Directional Scanning Transmission Electron Microscopy." Materials Science Forum 897 (May 2017): 173–76. http://dx.doi.org/10.4028/www.scientific.net/msf.897.173.
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The recently developed multi directional scanning transmission electron microscopy (MD-STEM) technique has been applied to exactly determine the Burgers vector (b) and dislocation vector (u) of a threading mixed dislocation in a silicon carbide (SiC) as-epitaxial wafer. This technique utilizes repeated focused ion beam (FIB) milling and STEM observation of the same dislocation from three orthogonal directions (cross-section, plan-view, cross-section). Cross section STEM observation in the [1-100] viewing direction showed that the burgers vector have a and c components. Subsequent plan view STEM observation in the [000-1] direction indicated that the b=[u -2uuw] (u≠0 and w≠0). Final cross section STEM observation in the [11-20] direction confirmed that the dislocation was an extended dislocation, with the Burgers vector experimentally found to be b = [1-210]a/3 + [0001]c which decomposes into two partial dislocations of bp1 = [0-110]a/3 + [0001]c/2 and bp2 = [1-100]a/3 + [0001]c/2. The dislocation vector u is [-12-10]a/3 + [0001]c. This technique is an effective method to analyze the dislocation characteristics of power electronics devices.
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Jayshri, D. Chaudhari. "Anatomical Changes in Seedling of Pisum Sativum Linn. Under the Nickel Stress." Indian Journal of Advanced Botany (IJAB) 3, no. 2 (2023): 1–3. https://doi.org/10.54105/ijab.B1018.103223.
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<strong>Abstract: </strong>A research investigation was conducted to find out how Nickel's different stresses affected the morphological alterations in Pisum sativum. Pisum sativum has a complex stem structure. In the transactional view, the stem of Pisum sativum is usually more or less square-shaped. The root's transverse section has a form which is slightly rounded. The structural abnormalities of Pisum sativum treated with different concentrations of Nickel indicated its toxic effect on the anatomical structure of the root and stem. Pisum sativum treated with lower to higher doses of Nickel showed few specific effects on stem anatomy. Plants treated with nickel had many structural changes in their roots.
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Verfaillie, Catherine M., Martin F. Pera, and Peter M. Lansdorp. "Stem Cells: Hype and Reality." Hematology 2002, no. 1 (2002): 369–91. http://dx.doi.org/10.1182/asheducation-2002.1.369.
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Abstract This update discusses what is known regarding embryonic and adult tissue-derived pluripotent stem cells, including the mechanisms underlying self-renewal without senescence, differentiation in multiple cell types both in vitro and in vivo, and future potential clinical uses of such stem cells. In Section I, Dr. Lansdorp reviews the structure and function of telomerase, the enzyme that restores telomeric ends of chromosomes upon cell division, highly present in embryonic stem cells but not adult stem cells. He discusses the structure and function of telomerase and signaling pathways activated by the enzyme, with special emphasis on normal and leukemic hematopoietic stem cells. In Section II, Dr. Pera reviews the present understanding of mammalian pluripotent embryonic stem cells. He discusses the concept of pluripotentiality in its embryonic context, derivation of stem cells from embryonic or fetal tissue, the basic properties of the stem cells, and methods to produce specific types of differentiated cell from stem cells. He examines the potential applications of stem cells in research and medicine and some of the barriers that must be crossed to achieve these goals. In Section III, Dr. Verfaillie reviews the present understanding of pluripotency of adult stem cells. She discusses the concept of stem cell plasticity, a term used to describe the greater potency described by several investigators of adult tissue-derived stem cells, critically reviews the published studies demonstrating stem cell plasticity, and possible mechanisms underlying such plasticity, and examines the possible role of pluripotent adult stem cells in research and medicine.
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Soares, Carlos Pedro Boechat, Gilson Fernandes da Silva, and Fabrina Bolzan Martins. "Influence of section lengths on volume determination in eucalyptus trees." CERNE 16, no. 2 (2010): 155–62. http://dx.doi.org/10.1590/s0104-77602010000200006.
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The aim of this work was to assess the influence of different section lengths on the determination of eucalyptus tree stem (with bark) volumes and its implications in forest inventory procedures. The 40 Eucalyptus grandis trees used, all from the municipality of Viçosa, Minas Gerais state, were 77 months old. The volume of the stems (with bark), whose maximum diameter was 3,0 cm, was obtained through the Smalian formula, with sections 1.0, 2.0 and 3.0 m long. Longer sections lead to overestimations of the volume of the trees' basal part and, consequently, of their total volume. Different statistical tests led to different conclusions regarding the similar volume estimates resulting from experiments using different section lengths4. Volumetric equations adjusted with longer sections may introduce bias errors in forest inventory procedures.
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Pavlov, Andrey, Janka Nôžková, Miroslava Šavrtková, Inna Matvienko, and Nina Brutch. "Photoperiod Influence on the Stem Structure of Fibre Flax." Agriculture (Pol'nohospodárstvo) 64, no. 4 (2018): 160–72. http://dx.doi.org/10.2478/agri-2018-0017.
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Abstract Plants of 13 fibre flax varieties were tested for their photosensitivity and differences of stems structure while grown in long and short daylight. It was detected that seven varieties did not change time of flowering in short 12 hours daylight in comparison with long 19 hours daylight. The extended diversity of fibre flax reactions on photoperiod changes and its relative independence of photosensitivity degree were found. Also, weak but significant correlation was found between photosensitivity coefficient and the degree of leaves number increase (r = 0.57). At the same time photo insensitive variety Belosnezhka improved leaves number up to 34%. Numbers of fibre bundles, their individual and total area on the stem cross section were not changed or reduced. Width, height, perimeter and shape of fibre bundles on a cross sections changed multidirectional. The areas of stem, its wooden part and cavity on a cross section showed no significant differences between plants grown in long and short day conditions. Evaluated flax characters were not strictly correlated with each other except those indicating the structure of fibre bundles. For breeding it is important that their relationships are not strongly influenced by the environment.
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Purusatama, Byantara Darsan, Jong-Ho Kim, Denni Prasetia, Alvin Muhammad Savero, Nyoman Jaya Wistara, and Nam Hun Kim. "Anatomical characteristics of unproductive Elaeis guineensis stems and their correlation with density." BioResources 19, no. 4 (2024): 9396–415. http://dx.doi.org/10.15376/biores.19.4.9396-9415.
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Oil palm is Indonesia’s predominant estate crop, but it generates a significant amount of unproductive stem waste. This study examined the anatomical characteristics and their relationship with density from core to bark across the bottom, middle, and top sections, providing insights for effective OPS utilization. Anatomical characteristics were observed with optical and scanning electron microscopy, and the density was measured using an electronic densimeter. The vascular bundle numbers (VBN) increased from core to bark and decreased from top to bottom. The fiber bundle area (FBA) increased from core to bark and from top to bottom. The fiber length (FL), width (FW), and wall thickness (FWT) decreased from bottom to top, whereas the fiber lumen diameter (FLD) increased. The FL of all sections decreased from core to bark. The radial variation of FW, FLD, and FWT varied in each section. The fiber at the inner section of the middle section and the whole top section mostly showed third-grade pulp quality, whereas the bottom section and outer part of the middle section were mainly fourth-grade pulp quality. The density was positively correlated with VBN. FBA, FL, and FW were negatively correlated with oven-dry density, although not significantly, while FWT and FLD were not correlated with OPS density.
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C.E.C. Ugwoke, SPG Anze, and A.E. Nweze. "Anatomical studies and nutritional analysis of the leaf extract of Plukenetia conophora." International Journal of Fundamental and Applied Sciences (IJFAS) 6, no. 1 (2017): 1–7. http://dx.doi.org/10.59415/ijfas.v6i1.102.
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Background and aim: Plukenetia conophora Mull. Arg. (African walnut) belongs to the Euphorbiaceae family. Thesignificance of wood anatomy in relation to taxonomy is by no means new or recent. Aim: The work evaluates theanatomy of the leaf, stem, root and the nutritional values of the leaves of Plukenetia conophora. Methodology: Leafepidermal strips were made by Impression technique and all sectionings (TS, TLS and RLS) were made with Reichertsliding microtome. Standard stains were used to differentiate the tissues. The proximate and mineral analyses werecarried out using standard methods. Results: Anatomical studies showed hypostomatic leaves with anomocyticstomata and no trichomes. Concentric vascular bundles were observed in the transverse sections of the leaf andpetiole. The various sections of the stem anatomy revealed diffuse-in-aggregate vessels with scanty axial parenchymain the transverse section, both uniseriate and biseriate rays in the transverse longitudinal section, and procumbent raysin the radial longitudinal section. Nutritional analysis showed presence of all the tested proximate and minerals. Theleaves contained proximate: carbohydrates (25.57 ± 0.05), protein (18.02 ± 0.02), ash (29.36 ± 0.33), moisture (18.06± 0.03), crude fibre (9.83 ± 0.17) and fat (7.41 ± 0.11) and minerals: calcium (19.18 ± 0.00), potassium (14.01 ± 0.00)and sodium (7.97 ± 0.03), Zinc (0.70 ± 0.01), magnesium (1.91 ± 0.01), iron (4.93 ± 0.04) and manganese (0.91 ±0.00). Conclusion: The anatomical results are quite useful in the delimitation of this species and nutritional resultssuggest the use of the leaves as a healthy food.
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Lee, Tae Hoon. "Administration of hATSCs results in recovery of cerebral infarction animal model." Journal of Medical Care Research and Review 3, no. 9 (2020): 420–24. http://dx.doi.org/10.15520/mcrr.v3i9.139.
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To examine pathway of stem cell transplanted to the brain, stem cells were infected with flourescence. hATSCs in the infarct region were mostly located at the border between intact brain tissue and the area of the infarction and in other sections within the infarct cavity. Examination of section with flourescence indicated that there was significant gliosis or infiltration of leukocytes around the implantation site of the stem cell. Implanted stem cell integrated and migrated to multiple areas of the brain including the contrallateral cortex. The cells persisted in the sites to which they migrated at 30 days after implantation. The heaviest concentrations of cells were transplanted into rats at 24hr after MCAO, more cells were migrated into injured area of brain cortex. Stem cell in the infarct region were found at the border between intact brain tissue and the area of infarction and within the infarct cavity.
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Dessie, Esubalew, Tamrat Tesfaye, Rotich Kipchirchir Gideon, Melkie Getnet Tadesse, and Yiping Qiu. "The Influence of Location along the Pseudostem on Enset Fiber Physio-Mechanical Properties: Application of Weibull Distribution Statistics." Applied Sciences 12, no. 14 (2022): 7323. http://dx.doi.org/10.3390/app12147323.
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Enset bundle fibers were divided lengthwise into four sections from bottom to top and the sections’ physio-mechanical parameters were studied and compared. The four equal fiber sections from the bottom were 0–375 mm (EV-I), 375–750 mm (EV-II), 750 mm–1125 mm (EV-III), and 1125–1500 mm (EV-IV). The mass distribution, cross-sectional area, linear density, and diameter all decreased along the fiber sections from bottom to top. The CIE Lab-color values of each fiber section were also examined, and the L* value for EV-II fiber section was higher. In terms of mechanical properties, the Enset bundle fiber’s tensile strength and work of rupture were analyzed, and both increased by 25% from the lower fiber section to the second fiber section (EV-1 to EV-II) along the length before decreasing significantly at the top sections. The investigation indicated that a higher Weibull modulus and tensile strength characteristics for EV-II were recorded while a low Weibull modulus and low strength characteristics of the Enset bundle fiber section EV-IV were observed. The investigation of Weibull distribution variability in the EV-IV fiber location was also confirmed using one-way ANOVA. Overall, the present study investigates the impact of fiber position along the plant stem on the mechanical and physical properties of Enset bundle fibers which can be used as an input for the optimization of unidirectional composites.
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Witzmann, Sarah, Laura Matitz, Christoph Gollob, et al. "Accuracy and Precision of Stem Cross-Section Modeling in 3D Point Clouds from TLS and Caliper Measurements for Basal Area Estimation." Remote Sensing 14, no. 8 (2022): 1923. http://dx.doi.org/10.3390/rs14081923.
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The utilization of terrestrial laser scanning (TLS) data for forest inventory purposes has increasingly gained recognition in the past two decades. Volume estimates from TLS data are usually derived from the integral of cross-section area estimates along the stem axis. The purpose of this study was to compare the performance of circle, ellipse, and spline fits applied to cross-section area modeling, and to evaluate the influence of different modeling parameters on the cross-section area estimation. For this purpose, 20 trees were scanned with FARO Focus3D X330 and afterward felled to collect stem disks at different heights. The contours of the disks were digitized under in vitro laboratory conditions to provide reference data for the evaluation of the in situ TLS-based cross-section modeling. The results showed that the spline model fit achieved the most precise and accurate estimate of the cross-section area when compared to the reference cross-section area (RMSD (Root Mean Square Deviation) and bias of only 3.66% and 0.17%, respectively) and was able to exactly represent the shape of the stem disk (ratio between intersection and union of modeled and reference cross-section area of 88.69%). In comparison, contour fits with ellipses and circles yielded higher RMSD (5.28% and 10.08%, respectively) and bias (1.96% and 3.27%, respectively). The circle fit proved to be especially robust with respect to varying parameter settings, but provided exact estimates only for regular-shaped stem disks, such as those from the upper parts of the stem. Spline-based models of the cross-section at breast height were further used to examine the influence of caliper orientation on the volume estimation. Simulated caliper measures of the DBH showed an RMSD of 3.99% and a bias of 1.73% when compared to the reference DBH, which was calculated via the reference cross-section area, resulting in biased estimates of basal area and volume. DBH estimates obtained by simulated cross-calipering showed statistically significant deviations from the reference. The findings cast doubt on the customary utilization of manually calipered diameters as reference data when evaluating the accuracy of TLS data, as TLS-based estimates have reached an accuracy level surpassing traditional caliper measures.
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Yani, Indri, Suci Pratiwi, Syarifah Zahra, Feizy Fachrunisa Naser, Hesti Nuraeni, and Bunda Cintawati. "Identifying Bambusa Sp. at TNGGP Resort PTN Selabintana Sukabumi through Mini Research Activities using Project Based Learning." Pedagogia: Jurnal Ilmiah Pendidikan 14, no. 2 (2022): 50–53. http://dx.doi.org/10.55215/pedagogia.v14i2.6766.
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Bamboo is a clear-trunked plant with grass stem type (calamus), which is a stem that is not hard, has real segments, and often hollow. The nature of the surface of the stem is hairy (laevis). The direction of growth is perpendicular (erectus). Bamboo has no branching pattern because it is a monocot. It has books (nodes) and segments (internodes). The cross section of the stem is round (teres) hollow or empty as it is stated by (Yutam Soleh 2013). This study aims to identify Bambusa sp. at Resort PTN Selabintana - Section PTN Region III - Division PTN Region II Sukabumi Gunung Gede Pangrango National Park. The method used is a descriptive exploratory method that describes the identification of Bambusa sp., and a roaming method that is exploring the Resort PTN Selabintana - PTN Section Region III - PTN Division Region II Sukabumi Gunung Gede Pangrango National Park which contains Bambusa sp. The results showed that the species Bambusa sp. found at Resort PTN Selabintana - PTN Section Region III - PTN Division Region III Sukabumi Gunung Gede Pangrango National Park were as many as 5 species, namely Gigantochloa pseudoarundinacea; Dendrocalamus asper; Dinochloa scandes; Bambusa blumeana; Schizostachyum brachycladum.
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Bieker, Dirk, and Steffen Rust. "Electric resistivity tomography shows radial variation of electrolytes in Quercus robur." Canadian Journal of Forest Research 40, no. 6 (2010): 1189–93. http://dx.doi.org/10.1139/x10-076.
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Electric resistivity tomograms of English oak ( Quercus robur L.) show a very distinct pattern of electric resistivity that has not been found in any other tree species yet and that cannot be related to the distribution of wood moisture content over the stem cross section. To reveal the factors underlying this two-dimensional pattern of electric resistivity, the variation of specific gravity and wood moisture content was analyzed in 18 cross sections of six roadside English oak trees after electric resistivity tomography. pH and electrolyte content were analyzed in two representative cross sections. Results show that electric resistivity correlates neither with wood moisture content nor density. The steep increase in electric resistivity at the sapwood–heartwood boundary correlates well with decreasing pH, potassium, and magnesium. The decreasing electric resistivity within the heartwood of English oak correlates with potassium and magnesium, increasing from the sapwood–heartwood boundary to the pith. More research is needed to identify species-specific electric resistivity patterns and their main factors if the method is to be used to detect wood fungal decay, historical ground water contamination, or other influences that may change the pattern of electric resistivity in the stem cross section.
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Rubaiyat, Sharmin Sultana, and Md. Mahabubur Rahman Dr. "Anatomy of Phyllanthus niruri L. (Euphorbiaceae)." EBAUB Journal 2 (January 1, 2020): 24–29. https://doi.org/10.5281/zenodo.6507152.
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The present study contracts with anatomical characterization of <em>Phyllanthus</em> <em>niruri </em>L., belongs to Euphorbiaceae family. Stem, leaf and root were the specimens for the anatomical study to observe treats in transverse section after staining with safranin. The anatomical studies revealed that the transverse section of stem showed the presence of one-layered epidermis covered by a thick cuticle. Hypodermis ranged 2-3 layers was present beneath the epidermis. Cortex was parenchymatous with profusely intercellular space. Cambium was present between xylem and phloem. Xylem was radially arranged and uniserrated to multiserrated. Xylem fibers was thick walled and lignified. The phloem was narrow. In transverse section of leaf, the epidermis layer was made up parenchymatous cells and the epidermal layer was covered with thick cuticle. Mesophyll cells (palisade and spongy parenchyma cells) were filled with chlorophylls. The large intercellular spaces occurred in the spongy parenchyma. <em>Phyllanthus niruri </em>L.<em> </em>showed paracytic stomata. The transverse section of root, it was encircled by cork cells. The cortical zone was narrow and the cortical cells intacted. The cortical regions arranged parenchymatous cells. The xylem was lignified and phloem was narrow and medullary rays were present.
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Jiang, Qian-li, Shan Jiang, Fei-li Chen, et al. "Semi-Solid Decalcification and Research System: a Novel Method to Study Fluorescence Protein Gene Modified Stem Cells In Bone." Blood 116, no. 21 (2010): 2625. http://dx.doi.org/10.1182/blood.v116.21.2625.2625.
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Abstract Abstract 2625 Background: It remains a huge challenge to observe fluorescent protein (GFP, RFP, etc.) gene-marked cells in bone, since bone is compact, poor lucency and porous, with different tissues such as vessels, nerve, cells, matrix and blood interlacing inside. However, it is very important to study the location, growth, migration and interaction of different stem cells and their offspring in bone. Aim: To better study different fluorescent protein gene-marked stem cells and microenvironment in bone, we establish a novel semi-solid decalcification (SSD) and research system. Methods: 1)Transplantation: Male BABL/C-GFP(H-2d) transgenic mice as donors and female FVB-RFP(H-2q) transgenic mice as recipients. Each RFP recipient mice were injected i.v. 5×10e6 allogeneic GFP bone marrow cells after 8 Gy TBI (n=10). Routinely, mice survival, weight, hemogram, GVHD manifestation were observed, with the fluorescence cells in peripheral blood and organs being traced. 2)Sections preparation: Total body perfusion fixation was performed with paraformaldehyde 21d after transplantation, and then different samples were collected for pathological examinations. The femurs were made frozen sections after semi-solid decalcification (SSD) system, while GMA plastic-embedding sections without decalcification, paraffin sections after EDTA decalcification, frozen sections after EDTA decalcification were also prepared as controls. Sections were observed by confocal microscopy. 3)Other researches: After SSD, observation and three-dimensional reconstruction were done by confocal microscopy; target tissue and cells were picked up for real-time quantified PCR for fluorescent protein genes and cell proliferation cytokines. Results: 1)Recipients RFP mice gained WBC recovery on (18.0±1.2)d, 90.0%±2.3% peripheral cells were GFP+ (n=10), 6 of 10 developed GVHD within 3m. 2)During SSD, hard component of the bone disappeared slowly, replaced gradually by semi-solid substance. SSD is even workable when the bone's diameter is large than 10cm. Frozen sections after SSD clearly showed unchanged position, form, and fluorescence of the GFP and RFP cells with repeatable hematoxylin and eosin(HE)and Wright-giemsa (RG) staining and immunohistochemical staining, fluorescence chromosomal in situ hybridization (FISH) after fluorescence observation and information from different tests of the same section can also be synthesized by computer. However, GMA cold embedding section could keep the cells where they are while losing the fluorescence, further more, embedding section only works well when the bone tissue is small (diameter<2mm). Frozen section after EDTA decalcification could keep the fluorescence with changed position and form during the progress. Paraffin sections can't keep neither the fluorescence nor the normal cell position and morphological characteristics. 3)Three-dimensional reconstruction shows the interesting relationships between different cells with different fluorescence and microenvironment by confocal microscopy. Quantified PCR described the cytokine expression profile of different fluorescence gene-marked cells. Conclusion: The SSD system shows great potency for the research of stem cells in vivo in bone while maintaining the morphological characteristics and structures between different cells without losing fluorescence signals. Another fantastic advantage is that a large number of techniques can be combined to our system to help us understand the homing, growth, proliferation, differentiation, migration and interaction of different target stem cells and their offspring. Disclosures: No relevant conflicts of interest to declare.
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Thai, Luom Thanh, Ngoc Thi Hong Dang, and Quang Minh Dinh. "The Role of Mangrove Forests in The Coast and Dykes West Sea Zone Protection: A Case Study in Kien Giang and Ca Mau Provinces." Revista de Gestão Social e Ambiental 18, no. 5 (2024): e05391. http://dx.doi.org/10.24857/rgsa.v18n5-001.
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Purpose: The study aimed to provide a picture total of the forest and erosion status of the beach and dykes of Kien Giang and Ca Mau.
 
 Method: There are 18 sample plots for testing. The map also includes 68 survey plots that are predefined and used as a basis for positioning in the field. The measurement indicators include tree species identification.
 
 Results and conclusion: The level of erosion in Ha Tien’s forests varies based on tree density and environmental factors. The forest with no erosion has a thickness of 9,600 trees/ha and a stem diameter of 19 cm, while the extremely erosion forest has 2,000 trees/ha and a stem diameter of 6 cm. Topographically, Ha Tien has little erosion, while U Minh is a low-lying area with high erosion. Erosion levels are 1-2 in January-April, 4-5 in May-October and 3 in November-December. Currently, the section is divided into 28 sub-sections, with Kien Giang having 23. One sub-section is level 1, 11 sub-sections are level 2, 1 is level 3, 3 are level 4, and 3 are level 5. In Ca Mau, two sub-sections are level 4, and 3 are level 5.
 
 Implications of the research: With climate change and rising sea levels, erosion levels tend to increase one level in sub-section areas in the coming years.
 
 Originality/value: This study assesses forest and erosion status in Kien Giang and Ca Mau provinces, Vietnam, providing local insights into environmental challenges. It uses a rigorous methodology, analyzes erosion levels, and classifies the area into sub-sections. The study also highlights the potential impact of climate change on erosion, promoting proactive adaptation and mitigation efforts.
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Phuong, Nguyen Lan, Le Thi Thu Hien, Nguyen Quang Linh, et al. "Implementation of STEM education: A bibliometrics analysis from case study research in Scopus database." Eurasia Journal of Mathematics, Science and Technology Education 19, no. 6 (2023): em2278. http://dx.doi.org/10.29333/ejmste/13216.
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In response to the long-term challenges of skills shortages and mismatches, many countries worldwide have made significant investments in STEM education. However, to obtain a comprehensive understanding of the progress of global research on the implementation of STEM education, it is essential to compile case studies on STEM education. Therefore, we conducted a bibliometric analysis of 750 publications from Scopus database to assess the bibliographic content of case studies on STEM education from 2006 to 2022. Our main findings show that the first case study on STEM education dates back to 2006, and research in this direction has grown enormously and continuously over the last five years (counting for 72.9%). The most influential articles in the field are cited mainly in the background citations section and help provide an initial perspective for readers to understand the insights discussed later in the study. The most popular journals publishing case studies in STEM education are of good quality, ranking highly in Scopus and Web of Science categories. The analysis results show three main research directions: STEM education in higher education, STEM education expands to STEAM, and STEM education activities in K12-education.
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Wang, Di, Ville Kankare, Eetu Puttonen, Markus Hollaus, and Norbert Pfeifer. "Reconstructing Stem Cross Section Shapes From Terrestrial Laser Scanning." IEEE Geoscience and Remote Sensing Letters 14, no. 2 (2017): 272–76. http://dx.doi.org/10.1109/lgrs.2016.2638738.
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Odell, A. E., S. P. Vander Kloet, and R. E. Newell. "Stem anatomy of Vaccinium section Cyanococcus and related taxa." Canadian Journal of Botany 67, no. 8 (1989): 2328–34. http://dx.doi.org/10.1139/b89-298.
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Twenty-nine Vaccinium species were scored for 14 stem and twig characters to determine whether or not vegetative features would support current taxonomic delimitations within the genus. The data obtained show not only that the verrucose characteristic of the twigs, one of the character states that defines Vaccinium section Cyanococcus, is caused by the presence of raised stomata, but also that members of this section have a peculiar mode of periderm development. In addition to the type of periderm development, the occurrence of lignification in twigs and stems was also noted, but was found not to be taxonomically useful at the sectional rank.
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Shaw, Jonathan A., Richard E. Andrus, and Blanka Shaw. "Sphagnum beringiense sp. nov. (Bryophyta) from Arctic Alaska, Based on Morphological and Molecular Data." Systematic Botany 33, no. 3 (2008): 469–77. http://dx.doi.org/10.1600/036364408785679842.
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A new species of Sphagnum section Subsecunda, S. beringiense, is described from arctic Alaska from the vicinity of Barrow along the northern coast. The species is distinguished morphologically by the light, yellow-green color of the gametophytes, multistratose stem cortex with 2–4 layers of enlarged thin-walled cells, round, medium-size (ca. 5 μm diameter) outer branch leaf pores, scattered inner branch leaf pores, typically few outer stem leaf pores, and abundant, round to elliptic inner stem leaf pores. Two unique plastid DNA haplotypes occur among Barrow area plants of S. beringiense, and these differ by a minimum of three nucleotide substitutions from those of other Alaskan Sphagnum species in the section Subsecunda. Microsatellite markers show that S. beringiense is genetically variable despite the fact that all plants were sampled from within an area of a few km2 and neither gametangia nor sporophytes have been observed. A key to the six Alaskan species of Sphagnum section Subsecunda is provided.
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Sullivan, Keith M., Robertson Parkman, and Mark C. Walters. "Bone Marrow Transplantation for Non-Malignant Disease." Hematology 2000, no. 1 (2000): 319–38. http://dx.doi.org/10.1182/asheducation.v2000.1.319.20000319.
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This article reviews the experience in hematopoietic stem cell transplantation (HSCT) for non-malignant disease. HSCT has long been applied as treatment of life-threatening congenital immunodeficiency and metabolic diseases. In Section I, Dr. Parkman reviews that experience for severe combined immunodeficiency, Wiscott-Aldrich syndrome, hyper IGM syndrome, Chédiak-Higashi disease and hereditary lymphohistiocytosis. The value of HSCT in genetic metabolic diseases such as osteopetrosis, osteogenesis imperfecta and the storage diseases are reviewed. In Section II, Dr. Walters reviews the experience over the last decade with allogeneic stem cell transplantation in patients with thalassemia major and sickle cell disease. In Section III, Dr. Sullivan reviews the more recent investigations using stem cell transplantation in patients with advanced autoimmune diseases such as systemic sclerosis, systemic lupus erythematosus, multiple sclerosis and juvenile rheumatoid arthritis. The pathogenesis and outcome with conventional care of these patients, the selection criteria and current results for HSCT, and the future directions in clinical research and patient care using this modality are addressed.
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Sullivan, Keith M., Robertson Parkman, and Mark C. Walters. "Bone Marrow Transplantation for Non-Malignant Disease." Hematology 2000, no. 1 (2000): 319–38. http://dx.doi.org/10.1182/asheducation.v2000.1.319.319.
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Abstract This article reviews the experience in hematopoietic stem cell transplantation (HSCT) for non-malignant disease. HSCT has long been applied as treatment of life-threatening congenital immunodeficiency and metabolic diseases. In Section I, Dr. Parkman reviews that experience for severe combined immunodeficiency, Wiscott-Aldrich syndrome, hyper IGM syndrome, Chédiak-Higashi disease and hereditary lymphohistiocytosis. The value of HSCT in genetic metabolic diseases such as osteopetrosis, osteogenesis imperfecta and the storage diseases are reviewed. In Section II, Dr. Walters reviews the experience over the last decade with allogeneic stem cell transplantation in patients with thalassemia major and sickle cell disease. In Section III, Dr. Sullivan reviews the more recent investigations using stem cell transplantation in patients with advanced autoimmune diseases such as systemic sclerosis, systemic lupus erythematosus, multiple sclerosis and juvenile rheumatoid arthritis. The pathogenesis and outcome with conventional care of these patients, the selection criteria and current results for HSCT, and the future directions in clinical research and patient care using this modality are addressed.