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C26H36N4O20Zn2, triclinic, P1‾$P\overline{1}$ (no. 2), a = 6.9872(4) Å, b = 8.9052(5) Å, c = 8.9052(5) Å, α = 94.441(4)°, β = 93.552(4)°$93.552(4){}^{\circ}$, γ = 90.045(5)°$90.045(5){}^{\circ}$, V = 1651.61(16) Å3, Z = 2, Rgt${R}_{gt}$(F) = 0.0748, wRref$w{R}_{ref}$(F2) = 0.2021, T = 293 K.

[Objective] The ecological value of cultivated land and compensation standards at multiple scales in a watershed was measured and analyzed in order to provide scientific reference for improving the compensation mechanism for cultivated land protection and promoting coordinated regional development. [Methods] The Liaohe River basin in Jilin Province was taking as an example, and used the equivalent sub-method, the market substitution method, and a landscape pattern index were used to establish a multi-scale cultivated land ecological value accounting system for the basin. The quantity and spatial allocation of cultivated land, differences in cultivated land quality, and the negative ecological externality of cultivated land were taken into account. On this basis, the cultivated land ecological compensation standard was formulated. [Results] ① Cultivated land had very important ecological values in the Liaohe River basin of Jilin Province, and the ecological values had significant spatial differences and scale-dependent effects. ② In 2020, the ecological value of cultivated land in the watershed was 20 502.78 yuan/ha, and the ecological value of cultivated land in each district and county had values between 4 261.97 and 16 873.59 yuan/ha, with values in the northwest region being higher than in the southeast region. ③ The compensation standard for cultivated land protection in the watershed was 4 319.36 yuan/ha, and the compensation standard of each district and county ranged from 814.68 to 3 471.85 yuan/ha. [Conclusion] For different spatial scales, differentiated ecological compensation standards and programs for cultivated land protection should be established, taking into account the ecological value of cultivated land and regional realities.

[Objective] The characteristics of cultivated land ecological supply and demand were analyzed in order to provide theoretical surpport for ensuring the sustainable supply of ecological functions of cultivated land and to maintain regional food security and ecological safety. [Methods] The study was conducted at Liaohe River basin in Jilin Province. and improves the ecological footprint model. Based on the productive-living-ecological functions of cultivated land, the production function footprint, living function footprint, and ecological function footprint of cultivated land were integrated, the ecological footprint model was improved, and the difference between cultivated land ecological supply and demand in the study area was clarified. [Results] ① The productive, living and ecological function footprints of cultivated land differed greatly at Liaohe River basin, among which the living function footprint of cultivated land was the largest and the ecological function footprint is the smallest. ② Cultivated land use was in a state of significant ecological surplus at Liaohe River basin, with the overall characteristics of “county (city) surplus and district deficit”. The production function deficit of cultivated land was the main cause of the ecological deficit of cultivated land. ③ The cultivated land ecological supply and demand were significantly unbalanced in space at Liaohe River basin, and the overall spatial variation was characterized as “surplus in the north and deficit in the south, with gradual progression”. [Conclusion] The ecological footprint model based on the productive-living-ecological functions of cultivated land was conducive to a more comprehensive exploration of the cultivated land ecological supply and demand. Based on the multifunctional nature of cultivated land, human occupation and consumption of cultivated land resources varied significantly, and the establishment of ecological compensation mechanisms for cultivated land in watersheds should fully take into account their spatial variation characteristics.

With the continuous improvement of technology and residents’ living standards. Should actively adapt to the opportunities and challenges brought by the Internet to the tourism marketing model, For the sustainable and rapid development of tourism on the wings of takeoff. In this paper, based on a brief explanation of the basic theory of database marketing, to achieve sustainable development of tourism marketing. Adopted the development of ecotourism boutique routes, Implementing multi-faceted marketing channels and means. Improvement of ecotourism infrastructure and service levels and other development measures. Create a tourism marketing model that responds to the trend of the times. Innovative marketing with big data technology can greatly stimulate the tourist crowd. Two times more efficient with dual cores. Get 56 times the execution efficiency with 64 cores. Get the efficiency of linear growth. The most direct way to increase the share of tourism companies in the consumer market. Maximize the value of marketing economic inputs and outputs. The results show that the improved PSO algorithm is more effective in database stability and dispersion. This makes it important for tourism marketing.

C27H28N4O16Zn2, monoclinic, C2/c (no. 15), a = 13.0720(3) Å, b = 15.7589(5) Å, c = 15.7589(5) Å, β = 95.373(3)°, V = 3062.48(18) Å3, Z = 4, Rgt(F) = 0.0499, wRref(F2) = 0.1059, T = 294 K.

Objective: Optimized cushioning packaging. Methods: Taking Hami melon and its packaging as the research object, conducted sweep frequency vibration test on 5-layer stacked packaging, measured the natural frequency, maximum power Spectral density and peak acceleration of the vertical and horizontal vibration of each layer of packaging, and established the relational model between the maximum power spectral density, peak acceleration and stacking layer. Results: The higher the packaging, the larger the maximum power spectral density and peak acceleration in both vertical and horizontal directions. The maximum power spectral density and peak acceleration in the vertical direction of the same layer of packaging were greater than those in the horizontal direction. The maximum power spectral density and peak acceleration were strongly positively correlated with the stacking layers. Conclusion: When conducting buffer packaging optimization design, the higher level of packaging requires better buffering performance; compared to the horizontal direction, the vertical direction requires better buffering performance; This regression model can accurately predict the vibration situation of each layer of packaging.

Abstract Background Focal atrial tachycardia (FAT) always originates from atrium specific sites and can be successfully cured by radiofrequency (RF) ablation. However, the middle cardiac vein (MCV) is a rare site of focal atrial tachycardia. Herein, we present a case of a 20-year-old young woman with FAT. Electrophysiological examination showed FAT arising from the proximal middle cardiac vein (pMCV), and successful RF ablation was applied with a low power and short-ablation. Case presentation A 20-year-old woman with no structural heart disease suffered recurrent supraventricular tachycardia for 1 year. Physical examination, laboratory studies and the echocardiography results of this patient were normal. A 12-lead electrocardiogram (ECG) showed a narrow QRS and long RP tachycardia which was always triggered by a sinus rhythm. The patient underwent an electrophysiological study and found the earliest activation was in the proximal MCV (pMCV). After a low power and short-ablation, AT was terminated and noninducible by programmed pacing with or without isoproterenol infusion. Conclusion This case presented a rare case of FAT arising from the pMCV. We demonstrate that low power and short-ablation are effective in AT arising from specific areas such as the coronary sinus ostium and pMCV.

Yeast plays an important role in fermented cereal products, especially fermented flour products, affecting the texture, aroma, appearance and nutrition of the products. In order to select grain microbial starter and improve the quality of fermented flour products, yeasts were isolated from traditional old flour and natural flour collected from different provinces and cities in China. Yeast identification was carried out by combining morphology and 26S rDNA sequence alignment. High-sugar-resistant, heat-resistant and high-quality yeasts were screened out to verify their application characteristics in steamed bread, toast bread and frozen dough. The results showed that 65 strains of yeasts were isolated, all of which were Saccharomyces cerevisiae, and 9 strains with strong fermentation ability were screened out, among which 5 strains could improve the specific volume, texture and taste of steamed bread, and the other 4 strains were resistant to high sugar and heat, which could improve the texture and flavor of toast bread. Besides, one strain had strong frost resistance, which could prolong the vitality period of frozen dough. The discovered strain is expected to be developed into a high-quality starter for fermented grain products, improve the performance of different kinds of fermented flour products, provide differentiated products for consumers, and promote the innovative development of grain processing industry.

This paper is concerned with the following quasilinear Schrödinger equations of the form: \begin{equation*} -\Delta u-u\Delta (u^2)+u=|u|^{p-2}u, \qquad x\in \mathbb{R}^3, \end{equation*} where $p\in\left(2,12\right)$. By making use of the constrained minimization method on a special manifold, we prove that the existence of positive radial solutions of the above problem for any $p\in(2,12)$.

C44H43N11O12Co2, triclinic, P 1‾ $\overline{1}$ (no. 2), a = 10.7333(11) Å, b = 13.6796(11) Å, c = 16.751(2) Å, α = 113.982(2)°, β = 90.578(2)°, γ = 105.7310(10)°, V = 2142.7(4) Å3, Z = 2, R gt(F) = 0.0460, wR ref(F 2) = 0.1015, T = 296(2) K.

Abstract Background Risk perception among nurses after the COVID-19 pandemic is a crucial factor affecting their attitudes and willingness to work in clinics. Those with poor psychological status could perceive risks sensitively as fears or threats that are discouraging. This article aimed to determine whether psychological outcomes, including post-traumatic stress disorder (PTSD), depression, anxiety, and insomnia, following the COVID-19 pandemic were differentially related to the risk perceptions of nurses working in clinics and increased perceived risk. Method The participants were 668 nurse clinicians from five local hospitals. Risk perceptions and psychological outcomes were measured by adapted questionnaires via the Internet. Latent profile analysis (LPA) identified subgroups of individuals who showed similar profiles regarding the perceived risks in nursing. Multinomial regression and probit regression were used to examine the extent to which sociodemographic and psychological outcomes predicted class membership. Results LPA revealed four classes: groups with low-, mild-, moderate-, and high-level risk perceptions. Membership of the high-level risk perception class was predicted by the severity of psychological outcomes. Anxiety significantly accounted for a moderate increase in risk perceptions, while the symptoms of insomnia, depression, and PTSD accelerated the increase to the high level of risk perception class. Conclusions By classifying groups of nurse clinicians sharing similar profiles regarding risk perceptions and then exploring associated predictors, this study shows the psychological outcomes after COVID-19 significantly impacted pandemic-associated risk perceptions and suggests intervening in nurses' psychological outcomes while simultaneously focusing on work-related worries is important following the outbreak of COVID-19.

This paper deals with a class of supercritical quasilinear Schrödinger equations $ -\Delta u+V(x)u+\kappa\Delta(\sqrt{1+{u}^{2}})\frac{u}{2\sqrt{1+{u}^{2}}} = \lambda f(u), \; x\in \mathbb{R}^{N}, $ where $ \kappa\geq2, \; N\geq3, \; \lambda > 0. $ We suppose that the nonlinearity $ f(t):\mathbb{R}\rightarrow \mathbb{R} $ is continuous and only superlinear in a neighbourhood of $ t = 0. $ By using a change of variable and the variational methods, we obtain the existence of positive solutions for the above problem.

[Introduction] To solve the problem of difficult site selection for grounding electrodes in HVDC transmission projects in Guangdong, this paper analyzes the connection of existing grounding electrodes to form a WAN grounding electrode for future DC project access to reduce the impact on electrical facilities and underground metal piping facilities around the electrode site. [Method] The feasibility of forming a wide-area grounding electrode by using existing grounding electrodes as sub-grounding electrodes was analyzed, several typical application scenarios of WAN grounding electrodes were proposed, and the natural shunted current calculation, current distribution averaging and multiple DC simultaneous operation conditions of each sub-grounding electrode were carried out. [Result] WAN grounding electrode can reduce the design requirements of Yuedong pole site and mitigate the impact of Yulongling grounding electrode on oil and gas pipeline and surrounding power system, and has the feasibility of implementation. However, the benefits are still not obvious without adding any current averaging resistors. [Conclusion] This study provides ideas and methods to reduce the difficulty of constructing new grounding electrodes by using WAN grounding electrodes.

The paper focuses on the modified Kirchhoff equation \begin{align*} -\left(a+b\int_{\mathbb{R}^N}|\nabla u|^2dx\right)\Delta u-u\Delta (u^2)+V(x)u=\lambda f(u), \quad x\in \mathbb{R}^N, \end{align*} where $a,b>0$, $V(x)\in C(\mathbb{R}^N,\mathbb{R})$ and $\lambda

To explore the anti-hepatocellular mechanism of five kinds of isoquinoline alkaloids， with the help of TCMSP， string， venny database and WebGestalt online analysis software to obtain the target and perform protein interaction network (PPI)， gene ontology (GO)， gene interaction (KEGG) function enrichment analysis， and use Cytoscape software to construct the network. At the same time， berberine in proberberine，Tetrandrine in dibenzyl alkaloids， sanguinarine in Phenphenanthroline， sinomenine in morphine and lycopine in pyrrolidine were obtained by literature review， induction， sorting and analysis. According to the structural mechanism of action， the potential of each type of representative isoquinoline alkaloid in the treatment of liver cancer and the mechanism of anti-liver cancer were expounded. Five active ingredients were screened and 52 targets such as p53 (tumor suppressor gene)， NCOA2 (nuclear receptor co-activator 2)， IL-2(interleukin 2) were obtained which mainly involved calcium ion signaling pathway， estrogen receptor signaling Pathways and PI3K/Akt signaling pathways. Through network pharmacology and literature collection， it is confirmed that isoquinoline alkaloids may be involved in the regulation of PI3K-Akt pathway，etc.， and can have therapeutic effects on liver cancer through multiple targets and multiple pathways. This paper can provide reference and basis for further clinical research on the anti-liver cancer effect of isoquinoline alkaloids.

In this paper, we study the following Schrödinger-Poisson system with critical exponent where $1 < p < 2$ and $\lambda > 0.$ Under suitable conditions on $k$, $h$ and $s$, we show that there exists $\lambda^{\ast}>0$ such that the above problem possesses infinitely many solutions with negative energy for each $\lambda\in(0, \lambda^{\ast})$. Moreover, we prove the existence of infinitely many solutions with positive energy. The main tools are the concentration compactness principle, $Z_{2}$ index theory and Fountain Theorem. These results extend some existing results in the literature.

We study a quasilinear Schrödinger equation with Robin boundary condition. Using the variational methods and the truncation techniques, we prove the existence of two positive solutions when the parameter λ is large enough. We also establish the existence of infinitely many high energy solutions by using Fountain Theorem when λ > 1.

We consider the following Schrödinger-Poisson system $$\left\{ \begin{array}{l}{\rm{ - }}\Delta u + V\left(x \right)u + \phi u = \lambda f\left(u \right)\; \; \; \; \; {\rm{in}}\; {\mathbb{R}^3}, \\ - \Delta \phi = {u^2}, \mathop {\lim }\limits_{|x| \to + \infty } \phi = 0, \; \; \; \; \; \; \; \; \; \; \; \; {\rm{in}}\; {\mathbb{R}^3}.\end{array} \right.$$Unlike most other papers on this problem, the Schrödinger-Poisson system without any growth and Ambrosetti-Rabinowitz condition is considered in this paper. Firstly, by Jeanjean's monotonicity trick and the mountain pass theorem, we prove that the problem possesses a positive solution for large value of $\lambda$ . Secondly, we establish the multiplicity of solutions via the symmetric mountain pass theorem.

Nuclear receptor binding SET domain protein 1 (NSD1), which is a family member of histone methyltransferases, functions to methylate histone H3 on lysine 36 (H3K36). NSD1-related abnormalities are the major cause of Sotos syndrome, and also known to be associated with other human diseases. Inhibitors targeting histone methyltransferases DOT1L and EZH2 have been reported recently. However, no chemical probes targeting NSD1 have been found so far. Here, we identified three hits targeting the NSD1 SET domain using ligand-observed nuclear magnetic resonance (NMR) fragment-based screening. The binding affinities of the hit compounds to the NSD1 SET domain were determined by dose-dependent chemical shift perturbation analysis. Furthermore, the potential binding modes of the hit compounds to NSD1 were obtained by molecular docking. The hit compound 1 was found to bind to the binding pocket of S-adenosylmethionine (SAM), an endogenous ligand of the protein, in the NSD1 SET domain. The study provided valuable information for further structure-guided hit-to-lead evolution towards the potent and specific inhibitors of the NSD1 SET domain.

In this paper, we study a class of quasilinear elliptic equations with $\Phi$-Laplacian operator and critical growth. Using the symmetric mountain pass theorem and the concentration-compactness principle, we demonstrate that there exists $\lambda_i>0$ such that our problem admits $i$ pairs of nontrivial weak solutions provided $\lambda\in (0, \lambda_i)$.

Structural neuroimaging data have been used to compute an estimate of the biological age of the brain (brain-age) which has been associated with other biologically and behaviorally meaningful measures of brain development and aging. The ongoing research interest in brain-age has highlighted the need for robust and publicly available brain-age models pre-trained on data from large samples of healthy individuals. To address this need we have previously released a developmental brain-age model. Here we expand this work to develop, empirically validate, and disseminate a pre-trained brain-age model to cover most of the human lifespan. To achieve this, we selected the best-performing model after systematically examining the impact of seven site harmonization strategies, age range, and sample size on brain-age prediction in a discovery sample of brain morphometric measures from 35,683 healthy individuals (age range: 5-90 years; 53.59% female). The pre-trained models were tested for cross-dataset generalizability in an independent sample comprising 2101 healthy individuals (age range: 8-80 years; 55.35% female) and for longitudinal consistency in a further sample comprising 377 healthy individuals (age range: 9-25 years; 49.87% female). This empirical examination yielded the following findings: (1) the accuracy of age prediction from morphometry data was higher when no site harmonization was applied; (2) dividing the discovery sample into two age-bins (5-40 and 40-90 years) provided a better balance between model accuracy and explained age variance than other alternatives; (3) model accuracy for brain-age prediction plateaued at a sample size exceeding 1600 participants. These findings have been incorporated into CentileBrain (https://centilebrain.org/#/brainAGE2), an open-science, web-based platform for individualized neuroimaging metrics.

Abstract The multiplicity of solutions for a (p,q) $(p,q)$-Laplacian equation involving critical exponent −Δpu−Δqu=λV(x)|u|k−2u+K(x)|u|p∗−2u,x∈RN $$ -\Delta_{p}u-\Delta_{q}u=\lambda V(x) \vert u \vert ^{k-2}u+K(x) \vert u \vert ^{p^{\ast }-2}u,\quad x\in \mathbb{R}^{N} $$ is considered. By variational methods and the concentration–compactness principle, we prove that the problem possesses infinitely many weak solutions with negative energy for λ∈(0,λ∗) $\lambda\in(0,\lambda^{\ast})$. Moreover, the existence of infinitely many solutions with positive energy is also given for all λ>0 $\lambda>0$ under suitable conditions.

Due to the different roles that nontoxic phytoplankton and toxin-producing phytoplankton play in the whole aquatic system, a delayed reaction-diffusion planktonic model under homogeneous Neumann boundary condition is investigated theoretically and numerically. This model describes the interactions between the zooplankton and two kinds of phytoplanktons. The long-time behavior of the model and existence of positive constant equilibrium solution are first discussed. Then, the stability of constant equilibrium solution and occurrence of Hopf bifurcation are detailed and analyzed by using the bifurcation theory. Moreover, the formulas for determining the bifurcation direction and stability of spatially bifurcating solutions are derived. Finally, some numerical simulations are performed to verify the appearance of the spatially homogeneous and nonhomogeneous periodic solutions.

This paper is devoted to studying a class of modified Kirchhoff-type equations \begin{equation*} -\Big(a+b\int_{\mathbb{R}^{3}}|\nabla u|^{2}dx\Big)\Delta u+V(x)u-u\Delta(u^2)=f(x,u),\hspace{0.5cm} \mbox{in}\ \mathbb{R}^3, \end{equation*} where $a>0, b\geq 0$ are two constants and $V:\R^{3}\rightarrow \R$ is a potential function. The existence of non-trivial solution to the above problem is obtained by the perturbation methods. Moreover, when $u>0$ and $f(x,u)=f(u)$, under suitable hypotheses on $V(x)$ and $f(u)$, we obtain the existence of a positive ground state solution by using a monotonicity trick and a new version of global compactness lemma. The character of this work is that for $f(u)\sim|u|^{p-2}u$ we prove the existence of a positive ground state solution in the case where $p\in(2,3]$, which has few results for the modified Kirchhoff equation. Hence our results improve and extend the existence results in the related literatures.

In this article, we prove multiplicity of solutions for the sum of polyharmonic equation with critical Sobolev exponent. The proof is based upon the methods of weakly lower semi-continuous of the functionals and the Mountain Pass Lemma without (PS) conditions.