Influence of light intensity and water content of medium on total dendrobine of Dendrobium nobile Lindl

Objective: To ascertain the influence of light intensity and water content of medium on the total dendrobine of Dendrobium nobile(D. nobile).Method: The principal component analysis combined with total dendrobine accumulation was conducted to assess the yield and quality of D. nobile in all treatments. In the experiment, D. nobile plants were cultivated in greenhouse as tested materials, and complete test of 9 treatments was adopted with relative light intensities 75.02%, 39.74%,29.93% and relative water content of medium 50%, 65%, 80%. The plants were treated in June and harvested till December. Indexes including agronomic traits, fresh weight and dry weight of stem and leaf, ash content, extract, and dendrobine were measured.Results: Under the light intensity treatments of 75.02% with 50%, 65%, 80% water content of medium, the basal stems of plants were comparatively thicker with more leaves, and the fresh weight and dry weight of stems and leaves were significantly higher than other 6 treatments.Leaves in all treatments contained dendrobine. Under the light intensity treatments of 75.02%with 50%, 65%, 80% water content of medium, dendrobine content of leaves was lower while dendrobine contents of other treatments were more than 0.60%. After comprehensive assessment through the principal component analysis and total dendrobine accumulation, the results showed that 3 treatments with relative light intensity of 75.02% ranked the top three.Conclusions: In brief, the moderately strong light intensity and water content of medium from low to medium can facilitate the growth and yield of D. nobile plants, while light intensity from moderately weak to weak can enhance the dendrobine content.

Bidirectional parallel multi-branch convolution feature pyramid network for target detection in aerial images of swarm UAVs

In this paper,based on a bidirectional parallel multi-branch feature pyramid network(BPMFPN),a novel one-stage object detector called BPMFPN Det is proposed for real-time detection of ground multi-scale targets by swarm unmanned aerial vehicles(UAVs).First,the bidirectional parallel multi-branch convolution modules are used to construct the feature pyramid to enhance the feature expression abilities of different scale feature layers.Next,the feature pyramid is integrated into the single-stage object detection framework to ensure real-time performance.In order to validate the effectiveness of the proposed algorithm,experiments are conducted on four datasets.For the PASCAL VOC dataset,the proposed algorithm achieves the mean average precision(mAP)of 85.4 on the VOC 2007 test set.With regard to the detection in optical remote sensing(DIOR)dataset,the proposed algorithm achieves 73.9 mAP.For vehicle detection in aerial imagery(VEDAI)dataset,the detection accuracy of small land vehicle(slv)targets reaches 97.4 mAP.For unmanned aerial vehicle detection and tracking(UAVDT)dataset,the proposed BPMFPN Det achieves the mAP of 48.75.Compared with the previous state-of-the-art methods,the results obtained by the proposed algorithm are more competitive.The experimental results demonstrate that the proposed algorithm can effectively solve the problem of real-time detection of ground multi-scale targets in aerial images of swarm UAVs.

Possible observation of shape-coexisting configurations in even–even midshell isotones with N=104:a systematic total Routhian surface calculation

Systematic total Routhian surface calculations for even–even N = 104 midshell isotones with 66≤Z≤82 have been carried out based on a more realistic diffuse-surface deformed Woods–Saxon nuclear potential in (β_2, γ, β_4) deformation space, focusing on the rotation-induced shapecoexisting phenomena. As an example and basic test, the oblate property at the ground state in ^(184)Hg is well reproduced and the microscopic origin is analyzed from the single-particle structure. The present calculated results are compared with available experimental information, showing a good agreement. It is systematically found that in this isotonic chain several bands with different shapes(e.g., prolate, oblate and superdeformed prolate bands, seven non-collective band) may show a strong competition and coexisting phenomenon at a certain domain of the rotational frequency.

Uncertainty evaluation and correlation analysis of single-particle energies in phenomenological nuclear mean field:an investigation into propagating uncertainties for independent model parameters

Based on the Monte Carlo approach and conventional error analysis theory,taking the heaviest doubly magic nucleus 208Pb as an example,we first evaluate the propagated uncertainties of universal potential parameters for three typical types of single-particle energy in the phenomenological Woods–Saxon mean field.Accepting the Woods–Saxon modeling with uncorrelated model parameters,we found that the standard deviations of singleparticle energy obtained through the Monte Carlo simulation and the error propagation rules are in good agreement.It seems that the energy uncertainty of the single-particle levels regularly evoluate with certain quantum numbers to a large extent for the given parameter uncertainties.Further,the correlation properties of the single-particle levels within the domain of input parameter uncertainties are statistically analyzed,for example,with the aid of Pearson’s correlation coefficients.It was found that a positive,negative,or unrelated relationship may appear between two selected single-particle levels,which will be extremely helpful for evaluating the theoretical uncertainty related to the single-particle levels(e.g.,K isomer)in nuclear structural calculations.

Nuclear collectivity in the even–even ^(164-178)Yb along the yrast line

The collective properties along the yrast line in well-deformed even–even ^(164-178)Yb isotopes are investigated by pairing self-consistent total Routhian surface(TRS) calculations and extended E-gamma over spin(EGOS) curves. The calculated results from ground-state deformations, e.g., β_2, are in agreement with previous theoretical predictions and available experimental data.The basic behaviors of moment of inertia are reproduced by the present TRS calculations and discussed based on the aligned angular momenta. The centipede-like E-GOS curves indicate that the non-rotational components appear along the yrast sequences in these nuclei, which can explain the discrepancy in the moment of inertia between theory and experiment to some extent. The further extended E-GOS curves, which include the first-order rotation–vibration coupling, appear to provide possible evidence of vibrational effects in the well-deformed nuclei of ^(164-178)Yb.

Revisiting the island of hexadecapoledeformation nuclei in the A≈150 mass region:focusing on the model application to nuclear shapes and masses

Based on the potential-energy-surface calculation,the impact of different deformation degrees of freedom on a single-particle structure and binding energies in nuclei around^(152)Nd,located on one of the hexadecapole-deformation islands,is analyzed in a multi-dimensional deformation space.Various energy maps,curves and tables are presented to indicate nuclear properties.The calculated equilibrium deformations and binding energies with different potential parameters are compared with experimental data and other theories.It is found that the inclusion of the hexadecapole deformations,especially the axial one,can improve the theoretical description of both nuclear shapes and masses.In addition,our calculated potential-energy curve shows that a critical deformation-point,β_(2)≈0.4,exists—the triaxial(hexadecapole)deformation effect can be neglectable but the hexadecapole(triaxial)one plays an important role before(after)such a critical point.

Probes of axial and nonaxial hexadecapole deformation effects in nuclei around^(230)U

The structure properties for even–even nuclei around^(230)U,located on the hexadecapoledeformation island,are investigated using the potential-energy-surface calculation within the framework of the macroscopic-microscopic model.The impact of different deformation degrees of freedom(including axial and nonaxial quadrupole and hexadecapole deformations)on total energy,shell,and pairing contributions is analyzed,based on the projected energy maps and curves.The single-particle structure is presented and briefly discussed.To a large extent,a much better agreement with experimental data and other theoretical results is obtained if the hexadecapole deformations,especially the axial one,are taken into account.These results could provide useful insights into understanding the effects of different quadrupole and hexadecapole deformations.

Discovery of new characterizations of parameter distributions in a semiempirical mass model:an investigation by dividing an overdetermined system into numerous balanced subsystems

We propose and test a new method of estimating the model parameters of the phenomenological BetheWeizsacker mass formula.Based on the Monte Carlo sampling of a large dataset,we obtain,for the first time,a Cauchy-type parameter distribution formed by the exact solutions of linear equation systems.Using the maximum likelihood estimation,the location and scale parameters are evaluated.The estimated results are compared with those obtained by solving overdetermined systems,e.g.,the solutions of the traditional least-squares method.Parameter correlations and uncertainty propagation are briefly discussed.As expected,it is also found that improvements in theoretical modeling(e.g.,considering microscopic corrections)decrease the parameter and propagation uncertainties.

Many-body correlations in shell model effective interactions derived by ab initio methods and the V_(low-k) approach

We investigate many-body correlations caused by two- and three-body （2-, 3bd） forces. Shell-model effective interactions derived from ab initio methods （coupled-cluster method, no-core shell model） are adopted. Vlow-k potentials, based on many-body perturbation theory, are also tested, especially for their cut-off dependence. We compare the central, tensor and spin-orbit interactions from microscopic theory to the fitted interactions. After the inclusion of the three-body force, the matrix elements become fairly close to those fitted directly to experimental data. Calculations of neutron-rich oxygen isotopes are performed, to clarify the effects of 3bd forces, tensor, and spin-orbit interactions on the nuclear binding and excitation energies. We find that the 3bd force can influence the binding energies greatly, which also determines the drip line position, while its effect on excitation energies is not very pronounced. The spin-orbit force, which is part of the 2bd force, can affect the shell structure explicitly, at least for neutron-rich systems.