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... 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. ...
... 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 ...
... 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 ...
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. ...
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 ...
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 ...
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
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 ...
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 ...
... 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 ...
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 ...
... 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. ...
... 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 ...
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 ...
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. ...
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 ...
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 ...
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 ...
... 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 ...
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 ...
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 ...