Propagation Method Research Articles

USE OF PLANT GROWTH REGULATORS TO OBTAIN MINI TUBERS OF Dioscorea remotiflora Kunth IN MICROPROPAGATED PLANTS

<p><strong>Background:</strong> Camote de cerro (<em>Dioscorea remotiflora</em> Kunth) stands out as a crop option in protected agriculture in Mexico due to its agronomic benefits and its versatility in the food and pharmaceutical industries. Despite its potential, it is not commercially cultivated in the country motivating the need to develop an efficient propagation method from vegetative planting material. Previous research suggests that the use of growth retardants stimulates root growth and carbohydrates accumulation in tubers, while applying gibberellic acid (GA<sub>3</sub>) is strongly related with greater tuber production. <strong>Objective: </strong>To evaluate the effect of different growth regulators to obtain <em>D. remotiflora</em> mini tubers.<strong> Methodology: </strong>Two experiments to obtain mini tubers were carried out. The first one evaluated mediums of culture <em>in vitro</em>: MS and MS + 0.5 mg L<sup>-1</sup> paclobutrazol (PBZ). In the second, effects of foliar application of GA<sub>3</sub>, PBZ and trinexapac ethyl (TNE) were evaluated. Both experiments were carried out in two accesions of <em>D. remotiflora</em> plants propagated <em>in vitro</em> and adapted to greenhouse conditions. <strong>Results:</strong> An increase in mini tubers yield and in their weight was observed when seedlings were propagated in MS + 0.5 mg L<sup>-1</sup> PBZ and GA<sub>3</sub> was applied to foliage. <strong>Implications:</strong> The use of growth retardants showed efficiency in developing mini tubers; nevertheless, more research focusing on concentrations and combinations of these substances is needed to improve the protocol to obtain planting material. <strong>Conclusions:</strong> The observed effect of growth retardants and gibberellic acid application in <em>Dioscorea remotiflora</em> plants suggests a favorable influence in the development of mini tubers. In the long term, this phenomenon could contribute significantly to promoting viability of its commercial cultivation and rehabilitation of previously exploited areas.</p>

Optimization of Ultrafast Singlet Fission in One-Dimensional Rings Towards Unit Efficiency

Singlet fission (SF) is an electronic transition that in the last decade has been under the spotlight for its applications in optoelectronics, from photovoltaics to spintronics. Despite considerable experimental and theoretical advancements, optimizing SF in materials like multichromophoric systems and molecular crystals remains a challenge, due to the complexity of its analysis beyond perturbative methods. Here, we tackle the case of one-dimensional rings, aiming to promote singlet fission and prevent its backreaction. We study ultrafast SF nonperturbatively, by numerically solving a spin-boson model, via exact propagation and tensor network methods. By optimizing over a parameter space relevant to organic molecular materials, we identify two classes of solutions that can take SF efficiency beyond 85% in the nondissipative (coherent) regime, and to 99% when exciton-phonon interactions can be tuned. After discussing the experimental feasibility of the optimized solutions, we conclude by proposing that this approach can be extended to a wider class of optoelectronic optimization problems. Published by the American Physical Society 2024

Few-shot Learning for Sign Language Recognition with Embedding Propagation

Sign language is a primary channel for the deaf and hard-hearing to communicate. Sign language consists of many signs with different variations in hand shapes, motion patterns, and positioning of hands, faces, and body parts. This makes sign language recognition (SLR) a challenging field in computer vision research. This paper tackles the problem of few-shot SLR, where models trained on known sign classes are utilized to recognize instances of unseen signs with only a few examples. In this approach, a transformer encoder is employed to learn the spatial and temporal features of sign gestures, and an embedding propagation technique is used to project these features into the embedding space. Subsequently, a label propagation method is applied to smooth the resulting embeddings. The obtained results demonstrate that combining embedding propagation with label propagation enhances the performance of the SLR system and achieved an accuracy of 76.6%, which surpasses the traditional few-shot prototypical network's accuracy of 72.4%.

Broadband Waveguide Chip Design with Phase Measurement Function for Enhancing Optical Interferometric Imaging

The waveguide chip with a phase measurement function has garnered significant attention in the field of imaging optics, emerging as a crucial component in optical interferometric imaging systems. Enhancing the working bandwidth of these waveguide chips is essential for improving the imaging quality of interferometric systems. However, most existing designs primarily focus on narrow bands, with no reported research on broadband designs. This paper introduces a novel broadband waveguide chip design that incorporates a phase measurement function. We explore the fundamental structure and working principle of this innovative design. Fabricated on a silicon substrate, the chip features a silicon dioxide cladding layer and a germanium-doped silicon dioxide core layer, strategically optimized for performance. Utilizing the Beam Propagation Method (BPM), we conduct detailed simulations to determine the optimal device parameters. The simulation results demonstrate the effectiveness of our design, showing a phase measurement deviation of approximately 5° at a center wavelength of 1550 nm across a 300 nm wavelength range. The loss of the device is approximately 0.8 dB. These findings provide a solid foundation for future experimental implementations and fabrications, offering both a theoretical framework and technical reference for advancing the practical use of broadband waveguide chips with phase measurement functions in optical interferometric imaging.

Gate voltage dependence on the density of state of 30° twisted bilayer graphene using Trotter–Suzuki tight-binding time propagation method

Abstract Twisted multilayer structures are considered a helpful framework for exploring strongly correlated many-particle systems, where phenomena of physics correlation emerge. Here, we present the Trotter–Suzuki tight-binding time propagation method for computing the density of states (DOS) in a 30° twisted bilayer graphene (TBG). This method solves the time-dependent Schrödinger equation by decomposing Hamiltonian matrices to derive the correlation function. The Fourier transform of this correlation function yields the DOS of the system up to ≈ 1000 000 atoms. Our calculation proves that geometry makes an outstanding contribution to our final results. Additionally, applying additional gate voltage induces shifts in Van Hove singularities, potentially leading to the emergence of new states at the Fermi energy level. The results demonstrate that TBG systems can be easily adjusted and modified for further investigation of optoelectronic features.

Rhizome Propagation Methods of Lowland Bamboo (Oxytenanthera abyssinica) in Central Tigray, Northern Ethiopia

Bamboo is a plant species that has a range of economic, environmental, and sociocultural importance. Bamboo can be propagated through sexual and asexual propagation methods. Both methods have their own advantages and disadvantages. This study aims to evaluate different rhizome cutting materials that are relatively suitable for large-scale plantations. The materials for propagating bamboo by vegetative means are whole or portions of the rhizomes, each with a single culm having two to six basal nodes, preferably 1- to 2-year-old culms from the peripheral portion of the clump having 2, 4, 6 basal nodes and 1.5-2 cm, 2-4 cm, and 4-6 cm in diameter. The design of the experiment is a split plot design with three replications and nine plots. This experiment is laid in 1029 m2 (21 m x 49 m). The size of each plot is 45 m2 (15 m by 5 m), and the distance between plots and plants in plots is 2 m. The number of nodes is assigned in the main plot, and the diameter of the planting material is assigned in the subplot. There are a total of 9 treatment combinations and a total of 108 planting materials. Significantly higher (P = 0.01) mean survival rate (59%) was observed in the planting material with two basal nodes and 2-4 cm diameter and the planting material with six nodes and 2-4 cm diameter. Further research is crucial to devise effective vegetative propagation methods for large scale plantations without compromising the survival capability of the planting materials.

Simulations of X-ray focusing by zone plates in rotationally symmetric optical field utilizing the matrix-free Finite Difference Beam Propagation Method

We present the use of a finite difference method based on Crank-Nicholson scheme and recurrence scheme for computationally efficient simulation of the X-ray propagation through a zone plate. By introducing boundary and central conditions and by avoiding large matrix operations, the method achieves considerable speed, little memory occupation and low background noise. Accommodating refractive index profiles of arbitrary shape, it can be applied to assist optimizing X-ray zone plates and understanding focusing mechanism.

Hybrid Coffee (<i>Coffea arabica</i> L) Plantlet Production via Indirect Somatic Embryogenesis in Ethiopia: Current Statue and Future Direction

Traditional hybrid coffee propagation methods using seed or vegetative cuttings has tremendous limitations. Seed propagation is associated with hand pollination which is time consuming and need large number of skilled labor. On the other hand, vegetative cuttings ensure uniformity, but; cuttings generate relatively low multiplication rates as they can only be obtained from orthotropic branches. Multiplication by tissue culture techniques could provide a best alternative to these traditional methods of coffee propagation as it allowed the production of relatively uniform plantlets on a large scale in a shorter period in any climatic condition. Among tissue culture techniques, indirect somatic embryogenesis of hybrid coffee plays substantial role in rapid industrial scale multiplication of high valued varities. Research on somatic embryogenesis of <i>C. arabica</i> hybrid has been conducted since the late 70s with the objectives to substitute the conventional vegetative propagation of selected varieties. In Ethiopia, in vitro propagation of hybrid coffee is recent phenomenon and research on indirect somatic embryogenesis is already well underway by different research groups. Here, we discussed the current status of coffee research on somatic embryogenesis in general and specifically, we provide recommendations for future research for the establishment of mass propagation protocol for F1 hybrids varities in Ethiopia that utilized wild endogenous lines.

Tibouchina granulosa Purple Glory Tree

This document provides an overview of Tibouchina granulosa, commonly known as the purple glory tree. It describes the plant’s characteristics, including its moderate growth rate, dense foliage, and large, vibrant purple flowers that bloom throughout much of the year. The plant can be trained into a small tree or maintained as a shrub, making it versatile for various landscape uses such as screens, specimen plants, or container gardening. The document also covers the plant’s cultural requirements, including its preference for full sun and well-drained soil, as well as its propagation methods and pest resistance. Emphasis is placed on its suitability for USDA hardiness zones 10B through 11. Original publication date October, 1999.

Basic Study on Evaluation Method for Fatigue Crack Initiation and Propagation in Carburized Steel for Large Rolling Bearings Considering Residual Stress in Three Directions

Basic Study on Evaluation Method for Fatigue Crack Initiation and Propagation in Carburized Steel for Large Rolling Bearings Considering Residual Stress in Three Directions

Second-Order Mass-Weighting Scheme for Atom-Centered Density Matrix Propagation Molecular Dynamics.

The atom-centered density matrix propagation (ADMP) method is an extended Lagrangian approach to ab initio molecular dynamics, which includes the density matrix in an orthonormalized atom-centered Gaussian basis as additional, fictitious, electronic degrees of freedom, classically propagated along with the nuclear ones. A high adiabaticity between the nuclear and electronic subsystems is mandatory in order to keep the trajectory close to the Born-Oppenheimer (BO) surface. In this regard, the fictitious electronic mass μ, being a symmetric, nondiagonal matrix in its most general form, represents a free parameter, exploitable to optimize the propagation of the electronic density. Although mass-weighting schemes in ADMP exist, a systematic procedure to define an optimal value of the fictitious masses is not available yet. In this work, in order to rationally evaluate the electronic mass, fictitious electronic normal modes are defined through the diagonalization of the Hessian of the electronic density matrix. If the same frequency is imposed on all such modes (compatible with the chosen integration time step), then the corresponding μ matrix can be calculated and then employed for the following propagation. Analysis of several ADMP test simulations reveals that such Hessian-based mass-weighting approach is able to ensure, together with a 0.1/0.2 fs time steps, a high separation between the (real) nuclear and the (fictitious) electronic frequencies, which determines a high adiabaticity. This high, unprecedented, accuracy in the propagation leads, in turn, to low errors in the estimated nuclear vibrational frequencies, making the ADMP method totally comparable to a fully converged BO molecular dynamics simulation but more computationally efficient. This work, therefore, contributes to a further development of the ADMP ab initio molecular dynamics method, aimed at improving its accuracy through a more rational evaluation of the fictitious electronic mass parameter.

Gradient descent optimization of acoustic holograms for transcranial focused ultrasound

Acoustic holographic lenses, also known as acoustic holograms, can change the phase of a transmitted wavefront in order to shape and construct complex ultrasound pressure fields, often for focusing the acoustic energy on a target region. These lenses have been proposed for transcranial focused ultrasound (tFUS) to create diffraction-limited focal zones that target specific brain regions while compensating for skull aberration. Holograms are currently designed using time-reversal approaches in full-wave time-domain numerical simulations. Such simulations need time-consuming computations, which severely limits the adoption of iterative optimization strategies. In the time-reversal method, the number and distribution of virtual sources can significantly influence the final sound field. Because of the computational constraints, predicting these effects and determining the optimal arrangement is challenging. This study introduces an efficient method for designing acoustic holograms using a volumetric holographic technique to generate focused fields inside the skull. The proposed method combines a modified mixed-domain method for ultrasonic propagation with a gradient descent iterative optimization algorithm. The findings are further validated in underwater experiments with a realistic 3D-printed skull phantom. This approach enables substantially faster holographic computation than previously reported techniques. The iterative process uses explicitly defined loss functions to bias the ultrasound field’s optimization parameters to specific desired characteristics, such as axial resolution, transversal resolution, coverage, and focal region uniformity, while eliminating the uncertainty associated with virtual sources in time-reversal techniques. The proposed techniques enable more rapid hologram computation and more flexibility in tailoring ultrasound fields for specific therapeutic requirements.

Analysis of the plant hormone expression profile during somatic embryogenesis induction in teak (Tectona grandis).

Plant somatic embryogenesis (SE) is an efficient regeneration system for propagation. It involves the regulation of a complex molecular regulatory network encompassing endogenous hormone synthesis, metabolism, and signal transduction processes, induced through exogenous plant growth regulators. Previous studies have focused primarily on traditional propagation methods for Tectona grandis, but there is limited knowledge on SE and its hormonal regulatory mechanisms. In our study, different SE stages, including the nonembryogenic callus (NEC), embryogenic callus (EC), and globular and heart-shaped embryo (E-SEs) stages, were induced in teak cotyledons incubated on MS medium supplemented with 0.1 mg/L thidiazuron (TDZ). Morphological and histological observations indicated that EC primarily originates from the development of embryogenic cell clusters. During SE induction, the levels of six classes of endogenous hormones, IAA, CTK, ETH, ABA, SA, and JA, changed significantly. Transcriptome analysis revealed that endogenous hormones participate in SE induction in teak through various biological processes, such as biosynthesis, metabolism, and signal transduction pathways. We found that IAA biosynthesis primarily occurs through the IAM pathway during these three stages. The ETH receptor kinase gene SERF1 exhibited the highest expression levels in E-SEs. The ABA-, SA-, and JA-related signal transduction genes ABI3, NPR1, and JAZ exhibited no differential expression during different stages. Moreover, key encoding genes of SE regulators, including WUS, WOX and SERK, were differentially expressed during SE. In conclusion, this study offers insights into the roles of endogenous hormones and their interactions during SE induction.

Prediction of sound around shooting ranges

The assessment of sound around shooting ranges can be challenging. On one hand, methods to predict the sound levels around shooting ranges are described in the standard ISO 17201 "Acoustics - Noise from shooting ranges". It consists of measurement and calculation methods to determine the source strength from muzzle blasts or explosives and supersonic projectiles, as well as a method for the sound propagation. The methods to calculate the muzzle and projectile sound are being updated this year. On the other hand, challenges remain to measure the source strength from weapons with a large caliber and the sound emitted from shooting facilities with a complex geometry. These issues and its approach are illustrated. Also, a noise management method is described, as a pilot study, that allows for a flexible use of different weapons for a given period of time, typically a year.

Road traffic noise prediction model "ASJ RTN-Model 2023" proposed by the Acoustical Society of Japan - Part 1: Framework of the calculation model

The Acoustical Society of Japan (ASJ) has had the Research Committee on Road Traffic Noise to develop a prediction model for road traffic noise for more than 50 years. As a result of the continuous research activities, a new version of model, "ASJ RTN-Model 2023", was published in this April. It is an upgrade version of the previous model, "ASJ RTN-Model 2018", proposed in 2019. In developing the latest version, existing knowledge was widely taken into account, in particular, the sound power levels of road vehicles under acceleration running conditions and calculation methods for sound propagation were improved in wide range. This new model is introduced in three papers with the same main title in this congress. In this paper, the framework of the model, the general procedure of prediction calculation, and the outlines of sound emissions and the calculation equations of sound propagation are presented.

Study on multi-cluster fracture propagation and quantitative evaluation method considering perforation erosion

This article pinpoints the problem of multiple clusters of crack extensions with perforation erosion, proposes a modified calculation formula for the variation of perforation diameter. Established a proposed three-dimensional numerical model to analyze the effect of different construction and completion parameters on fracture extension. The results show that: (1) With the pumping of sand-carrying fluid, the perforation erosion will lead to the increase of the flow coefficient and diameter of each cluster of perforation, which shows that the perforation erosion exacerbates the imbalance in flow distribution at the fracture inlet of each cluster as well as the non-uniform expansion of multi-cluster cracks. (2) The effect of perforation erosion increases with the enhancement of limited entry, and although the negative effect of perforation erosion is overall smaller than the positive effect of limited entry, it somewhat weakens the flow restriction ability of the perforation. (3) When the effect of limited entry is strengthened, considering the effect of perforation erosion the flow difference coefficient and the fracture length variation coefficient are significantly increased, and show a tendency to decrease (4) Use low proppant concentration to minimize damage to fractured pipe columns while meeting fracture inflow capacity.

The effect of several growth regulators and biostimulant on biochemical and physiological changes in acclimation of micropropagated Echinacea purpurea Moench. ‘Raspberry Truffle’

Micropropagation is currently one of the primary methods for plant propagation, known for its efficiency in producing disease-free and vigorous plants. However, the final stage of this—acclimatization, is critical due to the transfer from a controlled in vitro environment to an external one. To reduce mortality and alleviate acclimation stress, plant growth regulators (PGRs) or biostimulants can be employed. This study investigated the effects of exogenously sprayed PGRs: 0.001 mg L−1 abscisic acid (ABA), 0.001 mL L−1 brassinolide (BL), 0.001 mL L−1 24-epibrassinolide (24-epiBL), and 0.3 mL L−1 biostimulant Goteo on the physiological and biochemical responses of Echinacea purpurea ‘Raspberry Truffle’ plantlets during the acclimation process. The effects of treatments at various acclimation stages on chlorophyll (chl) and carotenoids content, hydrogen peroxide (H2O2), catalase (CAT), malondialdehyde (MDA), free amino acids, soluble proteins, total soluble sugar and reduced soluble sugars were tested in this research. The results confirmed changes in biochemical parameters, including an increase in chlorophyll and carotenoids in the acclimatization period where the highest level obtained by BL spraying. A decline in stomatal conductance was also observed, where ABA influenced the most on drop. It was also recorded the decrease in H2O2 and MDA concentration. CAT activity increased, especially with biostimulant treatment. We recorded an increase in total soluble proteins along acclimatization. Goteo affected the most on morphology parameters, ABA, BL and 24-epiBL increased acclimatization efficiency. Our studies indicate that potentially the most effective substances in the acclimatization of E. purpurea ‘Raspberry Truffle’ are brassinosteroids and ABA.

Deformation control of piezoelectric intelligent curved shell structure with multiple actuators based on neural network optimized by genetic algorithm

In aerospace engineering, it is important to achieve precise deformation control of curved shell. In this paper, the piezoelectric intelligent curved shell structure (PICSS) with multiple actuators was selected as the research object. Firstly, a finite element model of the structure was constructed, and the sample data was obtained based on simulation method for the back propagation (BP) neural network. Next, the structure of the BP neural network was determined as ‘6–13-24-3′ with the goal of obtaining the minimum mean square error. Then genetic algorithm was used to optimize the initial weights and thresholds of the BP neural network, and the input voltage of each actuator was predicted. The accuracy of voltage prediction was confirmed through collaborative simulation technology by testing the BP neural network before and after optimization. Finally, the deformation perception and control of the piezoelectric curved shell were verified through the PICSS.

Respon Pertumbuhan Bibit Single Bud Tanaman Aglaonema Varietas Donna Carmen Terhadap Aplikasi Zat Pengatur Tumbuh dan Pupuk Daun

Ornamental plants now become a trend among the public. The hobby of growing ornamental plants causes the demand for ornamental plant is increased day by day, especially the Aglaonema ornamental plant. In general, the propagation of Aglaonema plants is carried out by using separation of tillers and stem cuttings of 4-7 segments. Due to the high demand for Aglaonema plants, a new method of plant propagation is needed, in order to produce more plants in a short time, by using the single bud nursery method. Aglaonema stem cuttings are difficult to do because Aglaonema plants has bud's dormancy period. Dormancy of Aglaonema plant buds is triggered by apical dominance. The way to break bud dormancy on Aglaonema cuttings is using zpt auxin (Rootone-f). In addition, plants also need nutrients to grow, by providing fertilizer. Fertilization for ornamental plants generally uses foliar fertilizer (Gandasil D). This research was conducted using a Randomized Block Design (RBD) which consisted of 2 factors, the first factor zpt auxin (Rootone-f) which consisted of 4 levels (0 ppm, 100 ppm, 200 ppm, 300 ppm), and the second factor was Gandasil D foliar fertilizer which consisted of 3 treatment levels (0 g/l, 1 g/l, 2 g/l) so there are 12 treatment combinations. Each combination was repeated 3 times, thus forming 36 experimental units. The data were analyzed by analysis of variance (ANOVA) to determine the effect of the treatment and those whose effects were significantly different were further tested using the Ducan Multiple Range (DMRT) with a 95% confidence level. The combination of auxin zpt treatment (Rootone-f) with a concentration of 200 ppm and Gandasil D foliar fertilizer with a concentration of 2 g/l showed the best treatment combination on the parameters of observing fresh weight of Aglaonema plants. The concentration of zpt auxin (Rootone-f) 200 ppm gave the highest average value of shoot length, number of leaves, root length, and number of roots of Aglaonema plants. The concentration of Gandasil D 2 g/l foliar fertilizer gave the highest average leaf length and leaf width of Aglaonema plants.

Large-scale consensus in incomplete social network with non-cooperative behaviors and dimension reduction

Obtaining a consensus solution is a formidable challenge for large-scale decision-making (LSDM) in social network (SN). The reaching of large-scale consensus in SN is hindered by serious difficulties, including complex decision information, incomplete social relations, a multitude of decision-makers (DMs), and non-cooperative behaviors. This paper introduces a novel three-stage consensus framework that systematically addresses these challenges by data preprocessing, dimension reduction, and optimization modeling. Firstly, the cloud model is applied to convert the probabilistic linguistic information into numerical information, facilitating computational analysis. Meanwhile, an improved t-norm trust propagation method that incorporates the impact of opinion similarity is developed, ensuring the completeness of SN. Secondly, an improved Louvain algorithm is designed to divide large group into cohesive subgroups, enhancing the manageability of LSDM. On this basis, a three-stage consensus optimization that considers non-cooperative behaviors is proposed, which boasts threefold benefits: (i) Assures the synchronous achievement of local and global consensus. (ii) Implements self-adaptive management mechanism of non-cooperative behaviors. (iii) Provides acceptable adjusted opinions for subgroups and DMs. Finally, detailed numerical experiments and comparative analyses are given to demonstrate the effectiveness of the proposed method.