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1. A Novel Cyclopropanoid from Cinnamomum osmophloeum

Author:
C. Y. Chen; C. L. Kao; H. C. Yeh; H. M. Wu; H. T. Li
Source:
Chemistry of natural compounds 2021 v.57 no.5 pp. 848-850
ISSN:
0009-3130
Subject:
stems,   etc   ; Cinnamomum osmophloeum; chemistry;     Show all 3 Subjects
Abstract:
... A novel cyclopropanoid, 4-(2-(benzo[d][1,3]dioxol-5-yl)cyclopropoxy)-2,6-dimethoxyphenol (1) was isolated from the stems of Cinnamomum osmophloeum (Lauraceae). The structure of the novel cyclopropanoid was elucidated by chemical and physical evidence. ...
DOI:
10.1007/s10600-021-03493-w

2. Rearranged clerodane diterpenoid from Tinospora crispa

Author:
Abidah Parveen; Ying Huang; Omer Fantoukh; Manal Alhusban; Vijayasankar Raman; Yan-Hong Wang; Wei Wang; Zulfiqar Ali; Ikhlas A. Khan
Source:
Natural product research 2021 v.35 no.3 pp. 369-376
ISSN:
1478-6427
Subject:
stems,   etc   ; Tinospora crispa; diterpenoids; research;     Show all 4 Subjects
Abstract:
... A new rearranged clerodane diterpenoid, tinocrispide was isolated from the stems of Tinospora crispa along with thirteen known compounds including eight clerodane diterpenoids. Among the known compounds baenzigeride A, (6S, 9 R)-vomifoliol and steponine are being reported for the first time from T. crispa. Their structures were elucidated by 1 D and 2 D NMR and confirmed by HRESIMS. The ¹³C NMR da ...
DOI:
10.1080/14786419.2019.1633648

3. Impact of Different Pruning Practices on Height Growth of Paulownia Clon in Vitro 112®

Author:
Jiří Kadlec; Kateřina Novosadová; Radek Pokorný
Source:
Forests 2022 v.13 no.2 pp. -
ISSN:
1999-4907
Subject:
stems,   etc   ; Paulownia; bandages; forests; leaves; plant growth; plant height; plantations; planting; prunes; pruning; spring; sprouting; stem form; stumps;     Show all 15 Subjects
Abstract:
... We focused on the ability of one-year-old and two-year-old plants of Paulownia Clon in vitro 112® to sprout and grow branches, and on their pruning for their best possible growth on a plantation in Střelice u Brna. Furthermore, we carried out pruning on selected parts that comprised: spring pruning; reduction in the angle between the stem axis and one new growing sprout; and year-long pruning. The ...
DOI:
10.3390/f13020317

4. Structural features of the vegetative bodies of Hibiscus syriacus L. (Sev. Malvaceae Juss.) growing under the conditions in Uzbekistan

Author:
Rakhimov Abdikhofiz; Yoziev Lutfullo; Duschanova Guljan
Source:
BIO web of conferences 2021 v.30 pp. 04006
ISSN:
2117-4458
Subject:
stems,   etc   ; Hibiscus syriacus; leaf blade; webs; Uzbekistan;     Show all 5 Subjects
Abstract:
... The article studies the anatomical structure of the vegetative organs, stems, leaves and leaf blades of Hibiscus syriacus L. in Uzbekistan for the first time. ...
DOI:
10.1051/bioconf/20213004006

5. Enantiomeric lignans with antineuroinflammatory activities from Mappianthus iodoides

Author:
Feng Hu; Ya-Jie Hu; Bao-Jun Su; Ya-Qi Wang; Hai-Bing Liao; Dong Liang
Source:
Phytochemistry letters 2021 v.42 pp. 18-23
ISSN:
1874-3900
Subject:
stems,   etc   ; enantiomers; lignans; neuroglia; plant biochemistry; research; spectral analysis;     Show all 7 Subjects
Abstract:
... Three new pairs of lignan enantiomers (1a/1b‒3a/3b) and two pairs of known lignan enantiomers (4a/4b and 5a/5b) were isolated from the stems of Mappianthus iodoides. The structures of the enantiomers were elucidated by comprehensive spectroscopic analyses. Their absolute configurations were assigned by single-crystal X-ray diffraction analysis as well as comparison of the experimental and calculat ...
DOI:
10.1016/j.phytol.2021.01.006

6. PEG infiltration: an alternative method to obtain thin sections of cacti tissues

Author:
Giacomo Mozzi; Eunice Romero; Daniel M. Martínez-Quezada; Kevin R. Hultine; Alan Crivellaro
Source:
IAWA journal v.42 no.2 pp. 204-208
ISSN:
0928-1541
Subject:
stems,   etc   ; cacti and succulents; journals; methodology; polyethylene glycol; xylem;     Show all 6 Subjects
Abstract:
... Exploring the anatomical variability along the stem of cacti requires obtaining high-quality thin sections from hard and soft tissues. Several embedding, infiltration, and sectioning methods have been applied mainly to investigate the harder stem base of cacti, where thin cross-sections are relatively easy to obtain. However, analyzing the variation of anatomical features along cacti stems remains ...
DOI:
10.1163/22941932-bja10051

7. Microwave radiation associated with stepped leaders of negative cloud-to-ground flashes

Author:
Shamsul Ammar Shamsul Baharin; Mohd Riduan Ahmad; Taha Raad Khaleel Al-Shaikhli; Muhammad Abu Bakar Sidik; Muhammad Haziq Mohammad Sabri; Ammar Ahmed Nasser Al-Kahtani; Sulaiman Ali Mohammad; Gaopeng Lu; Hongbo Zhang; Vernon Cooray
Source:
Atmospheric research 2022 v.270 pp. 106091
ISSN:
0169-8095
Subject:
stems,   etc   ; antennae; avalanches; duration; electrons; microwave radiation; microwave treatment; research; sampling;     Show all 9 Subjects
Abstract:
... In this paper, Very-High Frequency (VHF) and microwave radiation pulses associated with stepped leader pulses (conventional breakdown) are examined. A total of 100 stepped leader pulses (SLPs) with the associated 100 quiet periods (QPs) from ten negative cloud-to-ground (CG) flashes within the reversal distance (<8 km) have been analyzed. The QP is defined as the period between two SLPs when no el ...
DOI:
10.1016/j.atmosres.2022.106091

8. Solid mechanics of the torus–margo in conifer intertracheid bordered pits

Author:
Paul J. Schulte; Uwe G. Hacke
Source:
new phytologist 2021 v.229 no.3 pp. 1431-1439
ISSN:
0028-646X
Subject:
stems,   etc   ; Picea mariana; air; conifers; depth; models; pressure; roots; seals; tracheids; width;     Show all 11 Subjects
Abstract:
... Bordered pits of many conifers include a torus–margo structure acting as a valve that prevents air from spreading between tracheids, although the extent of torus deflection as a function of applied pressure is not well known. Models were developed from images of pits in roots and stems of Picea mariana (Mill.) BSP. A computational solid mechanics approach was utilised to determine the extent of to ...
DOI:
10.1111/nph.16949

9. A New N-cis-Coumaroyltyramine Derivative from Fissistigma oldhamii

Author:
Cheng-Cong Zhu; Yu-Xi Luo; You Wu; Jing-Yu Yang; Xin-Shu Ji; Xue-Ming Zhou
Source:
Chemistry of natural compounds 2021 v.57 no.5 pp. 832-834
ISSN:
0009-3130
Subject:
stems,   etc   ; Fissistigma; chemistry; exhibitions;     Show all 4 Subjects
Abstract:
... A new N-cis-coumaroyltyramine derivative, fissistyramine (1), along with four known coumaroyltyramine derivatives (2–5), was isolated from the stems of Fissistigma oldhamii (Hemsl.) Merr. The structure of the new compound 1 was determined by 1D and 2D NMR as well as by HR-ESI-MS. The inhibitory effect of all the compounds on the proliferation of primary synovial cells was evaluated. Compounds 1, 2 ...
DOI:
10.1007/s10600-021-03491-y

10. A Computational Study of RNA Tetraloop Thermodynamics, Including Misfolded States

Author:
Gül H. Zerze; Pablo M. Piaggi; Pablo G. Debenedetti
Source:
Journal of physical chemistry 2021 v.125 no.50 pp. 13685-13695
ISSN:
1520-5207
Subject:
stems,   etc   ; Gibbs free energy; RNA folding; basins; canning; cans; journals; methodology; ribozymes; tempering;     Show all 10 Subjects
Abstract:
... An important characteristic of RNA folding is the adoption of alternative configurations of similar stability, often referred to as misfolded configurations. These configurations are considered to compete with correctly folded configurations, although their rigorous thermodynamic and structural characterization remains elusive. Tetraloop motifs found in large ribozymes are ideal systems for an ato ...
DOI:
10.1021/acs.jpcb.1c08038

11. Phyllotaxis development: a lesson from the Asteraceae family

Author:
Jing Liu; Quan Yuan; Yang Dong
Source:
Trends in plant science 2021 v.26 no.9 pp. 873-875
ISSN:
1360-1385
Subject:
stems,   etc   ; Gerbera; flowers; leaves; phyllotaxy;     Show all 5 Subjects
Abstract:
... Phyllotaxis refers to the spatial arrangement of leaves and flowers on a stem. A recent study by Zhang et al. described the developmental process underlying phyllotaxis establishment in the capitulum of Gerbera hybrida. This work represents a cornerstone for studying the development and diversification mechanisms of capitula in the Asteraceae. ...
DOI:
10.1016/j.tplants.2021.06.002

12. Morphological characteristics of ephyrae of Aurelia coerulea derived from planula strobilation

Author:
Satsuki Takauchi; Hiroshi Miyake; Naoya Hirata; Momoka Nagai; Nobuo Suzuki; Shouzo Ogiso; Shinichiro Ikeguchi
Source:
Fisheries science 2021 v.87 no.5 pp. 671-679
ISSN:
0919-9268
Subject:
stems,   etc   ; Scyphozoa; area; fisheries; mixtures;     Show all 5 Subjects
Abstract:
... Ephyrae are produced through the strobilation of polyps in the general life cycle of Aurelia coerulea. However, it has been reported that planulae can also metamorphose directly into ephyrae, without passing through the polyp stage. There is a mixture of ephyrae developed from planulae (planula-strobilated ephyrae) and ephyrae developed from polyps (polyp-strobilated ephyrae) in the ephyra populat ...
DOI:
10.1007/s12562-021-01541-6

13. A visual detection method for nighttime litchi fruits and fruiting stems

Author:
Cuixiao Liang; Juntao Xiong; Zhenhui Zheng; Zhuo Zhong; Zhonghang Li; Shumian Chen; Zhengang Yang
Source:
Computers and electronics in agriculture 2020 v.169 pp. 105192
ISSN:
0168-1699
Subject:
stems,   etc   ; Litchi; algorithms; fruiting; fruits; models; robots;     Show all 7 Subjects
Abstract:
... It is an important step for the precision operation of the litchi picking robot to accurately detect litchi fruits and fruiting stems in the natural environment. At present, the visual detection algorithms of litchi fruits and fruiting stems in the natural environment arestill limited by poor accuracy and robustness. This paper proposes a method to detect litchi fruits and fruiting stems at nightt ...
DOI:
10.1016/j.compag.2019.105192

14. Schipropins A–J, structurally diverse triterpenoids from Schisandra propinqua

Author:
Ren-Fen Ma; Kun Hu; Wen-Ping Ding; Bin Wang; Tao-Bin He; Xiao-Nian Li; Han-Dong Sun; Pema-Tenzin Puno
Source:
Phytochemistry 2021 v.182 pp. 112589
ISSN:
0031-9422
Subject:
stems,   etc   ; Schisandra; leaves; plant biochemistry; spectral analysis; triterpenoids;     Show all 6 Subjects
Abstract:
... Schipropins A–J, a series of undescribed lanostane and cycloartane-type triterpenoids, were isolated from the stems and leaves of Schisandra propinqua. Their structures, most of which were characterized by C-3/C-4 cleavage, were elucidated by extensive spectroscopic analyses. Noteworthily, the absolute configurations of schipropins A, D–G, and I were determined by single-crystal X-ray diffraction. ...
DOI:
10.1016/j.phytochem.2020.112589

15. The bHLH network underlying plant shade‐avoidance

Author:
Sara Buti; Scott Hayes; Ronald Pierik
Source:
Physiologia plantarum 2020 v.169 no.3 pp. 312-324
ISSN:
0031-9317
Subject:
stems,   etc   ; information; leaves; light; photoreceptors; shade; transcription factors;     Show all 7 Subjects
Abstract:
... Shade is a potential threat to many plant species. When shade‐intolerant plants detect neighbours, they elongate their stems and leaves in an effort to maximise their light capture. This developmental programme, known as ‘shade‐avoidance’ is tightly controlled by specialised photoreceptors and a suite of transcriptional regulators. The basic helix–loop–helix (bHLH) family of transcription factors ...
DOI:
10.1111/ppl.13074

16. Arahyside A, a new norsesquiterpene from Arachis hypogaea

Author:
Wen-Fang Jin; Zheng-Hui Luo; Yun-Peng Sun; Jin-Song Liu; Yang Yu; Gang Wang; Guo-Kai Wang
Source:
Natural product research 2020 v.34 no.21 pp. 3145-3148
ISSN:
1478-6427
Subject:
stems,   etc   ; Arachis hypogaea; cytotoxicity; leaves; research; spectroscopy; toxicity testing;     Show all 7 Subjects
Abstract:
... Six compounds were isolated from the stems and leaves of Arachis hypogaea, including a new norsesquiterpene, arahyside A (1), and five known compounds, 4-(2-methoxyethyl)benzene-1,2-diol (2), (1(R,S),2(R,S))-1-phenylpropane-1,2-diol (3), tachioside (4), 1,3-benzenediol (5), demethylmedicarpin (6). Extensive spectroscopic methods, containing HR-EI-MS, NMR and ECD were used for structural elucidatio ...
DOI:
10.1080/14786419.2019.1607860

17. Determination of chiral cathinone in fresh samples of Catha edulis

Author:
Abdulrhman M. Dhabbah
Source:
Forensic science international 2020 v.307 pp. 110105
ISSN:
0379-0738
Subject:
stems,   etc   ; Catha edulis; enantiomers; gas chromatography; quantitative analysis; solvents;     Show all 6 Subjects
Abstract:
... The main psychoactive compound in Khat is cathinone which consists of two enantiomers, S-(-)-cathinone being more stimulant than its R antipode. This study aimed to the enantioseparation and determination of these two stereoisomers in different parts of fresh Catha edulis. The samples were solvent extracted and cathinone was derivatized with menthyl chloroformate. The separation of the two diaster ...
DOI:
10.1016/j.forsciint.2019.110105

18. Tip‐to‐base xylem conduit widening as an adaptation: causes, consequences, and empirical priorities

Author:
Mark E. Olson; Tommaso Anfodillo; Sean M. Gleason; Katherine A. McCulloh
Source:
new phytologist 2021 v.229 no.4 pp. 1877-1893
ISSN:
0028-646X
Subject:
stems,   etc   ; diameter; drought; hydraulic resistance; hydraulic systems; leaves; length; models; natural selection; prediction; temperature; testing; turgor; vascular plants; xylem;     Show all 15 Subjects
Abstract:
... In the stems of terrestrial vascular plants studied to date, the diameter of xylem water‐conducting conduits D widens predictably with distance from the stem tip L approximating D ∝ Lᵇ, with b ≈ 0.2. Because conduit diameter is central for conductance, it is essential to understand the cause of this remarkably pervasive pattern. We give reason to suspect that tip‐to‐base conduit widening is an ada ...
DOI:
10.1111/nph.16961

19. Importance of data preparation when analysing written responses to open-ended questions: An empirical assessment and comparison with manual coding

Author:
Sara R. Jaeger; Morten A. Rasmussen
Source:
Food quality and preference 2021 v.93 pp. 104270
ISSN:
0950-3293
Subject:
stems,   etc   ; consumer attitudes; food choices; food quality; models; sample size;     Show all 6 Subjects
Abstract:
... In a world where consumer texts grow more numerous each day, automated text analysis can deliver valuable insights about consumer attitudes and behaviours. The present research was methodological in nature and focused on pre-processing of text data, which generally is the most time-consuming stage of analysis. Using responses to an open-ended question from 4341 consumers, document-term matrices (D ...
DOI:
10.1016/j.foodqual.2021.104270

20. Comparison of femoral stem subsidence between three types of press‐fit cementless total hip replacement in dogs

Author:
Megan M. Mitchell; Caleb C. Hudson; Brian S. Beale
Source:
Veterinary surgery 2020 v.49 no.4 pp. 787-793
ISSN:
0161-3499
Subject:
stems,   etc   ; analysis of variance; dogs; femur; prostheses; radiography; subsidence; surgery;     Show all 8 Subjects
Abstract:
... OBJECTIVE: To compare femoral stem subsidence and determine contributing factors in dogs undergoing total hip replacement (THR) with the traditional BFX, collared BFX, and BFX lateral bolt stems. STUDY DESIGN: Retrospective radiographic study. SAMPLE POPULATION: Ninety‐three dogs with 101 THR including dogs undergoing THR with a BFX lateral bolt femoral stem (n = 40), BFX collared stem (n = 21), a ...
DOI:
10.1111/vsu.13391