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This paper evaluated the regional tourism competitiveness of 22 county-level administrative regions in Ningxia Hui Autonomous Region, China. The study analyzed the connotation of regional tourism competitiveness from the perspectives of resources and economic and environmental benefits, and established an evaluation index system for comprehensive competitiveness. The study used entropy weight TOPSIS to measure the level of tourism competitiveness in Ningxia, and used spatial association and hot and cold analysis to describe the spatial pattern of comprehensive tourism competitiveness in Ningxia. The results indicated that Lingwu City, Xixia District, and Huinong District have high comprehensive tourism competitiveness, while Jingyuan County, Haiyuan County, and Hongsipu District exhibit the weakest comprehensive competitiveness. The study also showed that regional economic development level competitiveness had the greatest impact on the comprehensive competitiveness of county tourism in Ningxia. The northern region and the southern region of Ningxia were the regions with high-high clusters and low-low clusters of tourism competitiveness, respectively. Based on the comprehensive evaluation results, the development level of tourism of Ningxia county was classified into four types: advanced development type, marginal dependence type, improved optimization type, and backward development type. Finally, the paper put forward targeted optimization suggestions in order to provide reference for Ningxia tourism functional zoning and high-quality development.

With the in-depth development of the Western Development Strategy and Rural Revitalization, the tourism industry has become an important economic sector to drive local development in northwestern minority areas of China. This study established a database of tourism resources in Longde county and analyzed the spatial pattern of these tourism resources by using the scale index and kernel density. From the perspective of the natural and social environment, this paper quantitatively discusses the influencing factors of the spatial pattern of tourism resources in the county based on a multiple linear regression model. The results showed that: (1) There were 2049 tourism resources distributed in Longde County, and building and facility resources were the most prevalent. (2) The hierarchical structure of tourism resources in the county showed a “pyramid” distribution, where excellent tourism resources accounted for 22.60% of the total resources. (3) The spatial pattern showed an agglomeration distribution, and the spatial differences of all kinds of resources were significant. The resources were mainly distributed in Chengguan Town and Wenbao Township. (4) Topographic conditions, convenient transportation, population density and water system distribution were important factors that affected the spatial pattern of tourism resources. It was suggested that the government issue corresponding policies to optimize the spatial pattern of tourism resources; balance the relationship between the exploitation of tourism resources, tourism development and local economy, and the social and ecological environment; and promote the sustainable development of tourism in the northwestern ethnic areas in China.

Keratin 15 (KRT15) overexpression links with tumor initiation, metastasis, and poor survival in several solid carcinomas. While its clinical relevance is scarcely reported in endometrial cancer (EC). Therefore, the current study aimed to investigate the abnormal expression of KRT15 and its correlation with clinical characteristics, survival in EC patients. Totally, 135 surgical EC patients were enrolled. KRT15 protein expression in formalin-fixed and paraffin-embedded tumor and adjuvant tissues was detected by immunohistochemical staining; meanwhile, KRT15 mRNA expression in fresh-frozen tumor and adjacent tissues was detected by reverse transcription-quantitative polymerase chain reaction. KRT15 protein and mRNA expressions were higher in tumor tissue compared with adjacent tissue (both P.001). Elevated KRT15 protein expression was correlated with the occurrence of lymphovascular invasion (P = .010) and more advanced International Federation of Gynecology and Obstetrics stage (P = .018); meanwhile, elevated KRT15 mRNA expression was linked with more advanced International Federation of Gynecology and Obstetrics stage (P = .038) and marginally associated with the occurrence of stromal cervical invasion (P = .052). Besides, KRT15 protein and mRNA expressions were not correlated with other clinical features (all P.05). KRT15 protein high was marginally correlated with poor accumulating disease-free survival (DFS) (P = .091) and overall survival (OS) (P = .059); meanwhile, the correlation of KRT15 mRNA expression with accumulating DFS (P = .212) and OS (P = .092) was even weaker. However, multivariate Cox's regressions showed that tumor KRT15 protein (high vs low) was independently correlated with poor DFS (P = .045) and OS (P = .043). KRT15 is abnormally increased in EC tissue, meanwhile, its upregulation links to the occurrence of lymphovascular invasion, stromal cervical invasion, and poor prognosis in EC patients.

A-kinase-interacting protein 1 (AKIP1), as a recently discovered oncoprotein, promotes cell malignant behaviors in gynecological malignancies. To the best of our knowledge, no study reports its clinical value in patients with endometrial carcinoma. The present study aimed to explore the association between AKIP1 expression and clinical features and survival in patients with endometrial carcinoma, and to assess the effect of AKIP1 knockdown on the regulation of chemosensitivity

Selecting the most scenic viewpoints in an island forest park can provide a scientific basis for island ecotourism planning. In this paper, considering the influence of climatic conditions on sightseeing, landscape factors, accessibility factors, and seasonal change factors are selected from the perspective of time and space to analyze the landscape spatiotemporal characteristics, and the construction of a landscape spatiotemporal perception evaluation model and the analysis of influencing factors are carried out. The results show that the evaluation model for landscape spatiotemporal perception factors can quantitatively describe tourists’ comprehensive perception of a landscape in different regions and time periods in ecotourism areas, and can identify the spatiotemporal characteristics of landscape perception. Case studies preliminarily prove the feasibility of the model and calculation process. This method provides a strong reference for the development and planning of island tourism, especially providing new ideas and methods for the design of sightseeing routes in the development and planning of small-scale scenic viewpoints, which can enrich island tourism planning.

In recent years, immune checkpoint inhibitor (ICI) therapy has revolutionized the treatment of patients with advanced-stage non-small cell lung cancer (NSCLC). The relationship between TP53 mutation and prognosis of non-small cell lung cancer (NSCLC) remains controversial. We aimed to identify advanced-stage NSCLC patients harboring TP53 mutation who would benefit from ICI treatment. Gene mutations and tumor mutational burden (TMB) data of NSCLC patients who received at least one dose of ICI therapy at the Memorial Sloan Kettering Cancer Center between 2013 and 2017 were extracted from the cBioPortal online platform. Gene clustering analyses were performed for patients with short and long overall survival (OS). The top ten significantly different mutated genes were identified. Furthermore, we analyzed the different OS of coexisting TP53 and other significantly different mutated genes to identify NSCLC patients with TP53 mutations who would benefit from immunotherapy. A total of 350 patients were enrolled in the study. Of these a total of 219 (62.6%) patients were found to harbor TP53 mutations, whereas 131 (37.4%) had wild-type TP53. There was no statistically significant difference in OS between TP53 mutated or wild-type NSCLC patients who underwent ICI treatment. However, coexisting TP53 and ZFHX3 mutations were independent prognostic factors. Higher somatic TMB (highest 20% in each histology) and combination of anti-CTLA-4 and anti-PD-1/PD-L1 therapy were also associated with longer OS in multivariate analysis. Coexisting TP53 and ZFHX3 mutations are independent prognostic factors for advanced-stage NSCLC patients undergoing ICI treatment. These findings could help identify patients harboring TP53 mutations that would benefit from ICI treatment.

With the continuous development of photovoltaic (PV) grid-connected technology, the PV grid-connected capacity has increased sustainably. Due to the stochastic volatility and indirectness of PV power, the PV grid-connected technology has greatly influenced system instability mode and oscillation center distribution. The simulation is carried out under two conditions: the location of PV grid-connected; the relative position between fault point and PV power, which is based on the out-of-step oscillation criterion of the bus voltage frequency, the PV power supply model and its control strategy. The results show that the change of PV grid-connected location will change the system's equivalent external characteristics and cause the oscillation center to migrate between different lines. The frequency of oscillation center migration increases when the fault location is closer to the PV grid-connected location.

Due to the characteristics of randomness, volatility and low inertia, the large-scale integration of new energy units has changed the original power flow distribution and deteriorated the transient stability of the system, resulting in the migration of the system oscillation center, which can even affect the accurate action of the splitting control. Aiming at the problem that the integration of doubly-fed induction generator (DFIG) affects the migration law of the oscillation center, firstly the Thevenin equivalent model of DFIG is constructed and the operating characteristics are analyzed. And then the equivalent admittance model of DFIG is constructed. Finally, based on the equivalent admittance model, the migration law of the oscillation center in the DFIG-based wind power system is analyzed. The results show that the out-of-step center (OOSC) moves away from the DFIG-based wind farm integration point when DFIG generates reactive power and moves close to the integration point when DFIG absorbs reactive power. While the migration range of the oscillation center extends to the entire line.

Suffering from fragile environment, poor accessibility and infrastructure, as well as social, political and economic marginality, the interprovincial mountain geographical entities are difficult areas for the regional governance in China. By analyzing the spatial patterns and the influencing factors of the interprovincial mountain geographical names (IMGNs), the goal of this research is to clarify the geographical features of IMGNs and offer alternatives for the management of interprovincial mountain regions in China. The spatial visualization, the analysis of spatial agglomeration and the influencing factors of IMGNs were all implemented under a geographical information system. Results showed that there were 6869 IMGNs in China according to the database of “China’s Second National Survey of Geographical Names (2014–2018)”, including 4209 mountain geographical names, 1684 mountain peak geographical names and 976 the other mountain geographical names. Hunan Province had the largest number of names while Shanghai had the smallest number of names. In addition, the spatial variance of the mountain peak names and the mountain names were larger than that of the other mountain geographical names, and the IMGNs showed a significant clustering phenomenon in the southern part of China. The relative elevation and the population had an impact on the distribution of the IMGNs. The largest number of the names occurred where the relative elevation was between 1000–2000 m and where the population was between 40–50 million. Density of unnamed interprovincial mountain geographical entities declined from west to east in China. The analysis of generic names of different types of IMGNs implied that the naming of IMGNs is inconsistent. Based on these analyses, it is suggested that the government should take the IMGNs as management units, strengthen the naming of unnamed interprovincial mountain geographical entities, standardize the generic names of IMGNs and identify areas of poverty based on the survey of IMGNs.

Electric power industry in China develops rapidly, thus China’s grid structure tends to be complicated. This paper classifies the different functional properties of the power grid, discusses the different functional properties of the power grid and their impact on the grid structure, constructs the network optimization model based on the functional properties and conducts simulation verification, thus providing a grid planning method based on different functional properties of the grid.

Controlled splitting is an important measure to ensure the safety of the Energy Internet. An improved ant colony optimization algorithm is proposed in order to reduce the high complexity of the solution process in this paper. Firstly, establish a mathematic model for controlled splitting surface searching and map it to ant colony optimization algorithm with a single objective function and multiple constraints. Then, based on the connectivity constraint, the optimal controlled islanding solution can be obtained. Simulation results of IEEE 118-bus system verify the effectiveness and rapidity of the proposed method.

Furoylhydrazones of general formula 4-R–C6H4–CH=NNH–CO–2-C4H3O [R = H (HL1) and OCH3 (HL2)] have been conveniently prepared from furan-2-carbohydrazide. The reaction of HL1 with Li2[PdCl4] and CH3COONa provided the di-µ-chloro-bridged cyclopalladated complex [Pd(C6H4–CH=N–NH–CO–2-C4H3O)(µ-Cl)]2 (1) through aryl C–H bond activation, whereas the unusual tetranuclear cluster [Pd(4-CH3O–C6H4–CH=N–NH–CO–2-C4H3O)(µ-Cl)]4 (2) was obtained from the reaction with ligand HL2. The crystal structures of 1 and 2 show a slightly distorted square-planar coordination geometry around the palladium ion to which the furoylhydrazone is attached in a bidentate fashion. The two palladium(II) complexes were able to catalyze the Suzuki–Miyaura coupling reactions of phenylboronic acid with aryl halides to afford the desired biaryl derivatives in excellent yields (up to 99.2 %).

The ferrocene tertiary amines of general formula [(η5 C5H5)Fe(η5 C5H4) CH2N(CH3) CH2 C(R) CH C6H5, R H (3a) and R CH3 (3b)] were conveniently prepared from the corresponding ferrocenylimines [(η5 C5H5)Fe(η5 C5H4) CH2N CH C(R) CH C6H5, R H (1a) and R CH3 (1b)] in two steps. Metalation of 3a, 3b with Li2PdCl4 and CH3COONa, followed by treatment with PPh3, gave the ortho palladium (II) complexes Pd{[(η5 C5H5)Fe(η5 C5H3) CH2N(CH3) CH2 CH CH C6H5]}ClPPh3 (5a) and Pd{[(η5 C5H5)Fe(η5 C5H3) CH2N(CH3) CH2 C(CH3) CH C6H5]}ClPPh3 (5b), respectively. However, Palladation of ferrocenylimines 1a and 1b afforded the heteroannular palladium (II) complexes. This protocol proved that the isomerism around the C N moiety might indicate that the palladium entered into the lower ferrocene ring, giving the heteroannular palladium (II) complexes. Additionally, theoretical studies indicated that the C H bond in the substituted ferrocene ring for the ligands 3a and 3b was prior to metalation. As for the catalyst, the palladacycles showed high efficiency in Suzuki-Miyaura cross-coupling reaction using low catalyst loading 0.1 mol%.

As part of the cultural landscape, administrative toponyms do not only reflect natural and sociocultural phenomena, but also help with related management and naming work. Historically, county-level administrative districts have been stable and basic administrative regions in China, playing a role in the country's management. We explore the spatio-temporal evolutionary characteristics of the county-level administrative toponyms cultural landscape in China's eastern plains areas. A Geographical Information System (GIS) analysis, Geo-Informatic Tupu, Kernel Density Estimation, and correlation coefficients were conducted. We constructed a GIS database of county-level administrative toponyms from the Sui dynasty onward using the Northeast China, North China, and Yangtze Plains as examples. We then summarized the spatio-temporal evolutionary characteristics of the county-level administrative toponyms cultural landscape in China's eastern plains areas. The results indicate that (1) the number of toponyms has roughly increased over time; (2) toponym densities on the three plains are higher than the national average in the corresponding timeframe since the Sui; and (3) county-level administrative toponyms related to mountains and hydrological features accounted for more than 30% of the total in 2010. However, the percentage of county-level administrative toponyms related to natural factors on the three plains has decreased since the Sui. To explore the factors influencing this spatio-temporal evolution, we analyzed the correlations between the toponyms and natural factors and human/social factors. The correlation degree between toponym density and population density is the highest, and that between toponym density and Digital Elevation Model (DEM) the lowest. Temperature changes were important in toponym changes, and population changes have influenced toponym changes over the last 400 years in China.

The ferrocenylimines of general formula [(η5-C5H5)Fe(η5-C5H4)-CH2N═CH-C(R)═CH-C6H5] with R = H (2a) and CH3 (2b) were conveniently prepared from ferrocenylmethylamine. Reaction of 2a,b with lithium tetrachloropalladate in methanol in the presence of anhydrous sodium acetate resulted in the formation of the di-μ-chloro-bridged heteroannular cyclopalladated complexes 3a,b via the unsubstituted ferrocenyl C–H bond activation of the related ligands. Treatment of 3a,b with triphenylphosphine gave Pd{[(η5-C5H4)Fe(η5-C5H4)CH2N═CH-CH═CH-C6H5]}ClPPh3 (4a) and Pd{[(η5-C5H4)Fe(η5-C5H4)-CH2N═CH-C(CH3)═CH-C6H5]}ClPPh3 (4b), respectively. The crystal structures of 4a,b confirmed the formation of a carbon–palladium bond by using a carbon atom in the unsubstituted cyclopentadienyl ring. Additionally, theoretical studies using density functional theory calculations were carried out in order to account for the regioselectivity of cyclometalation. As for the catalysts, using 0.1% of palladacycles 4a,b in the presence of K3P...

As a part of cultural landscapes, toponyms with abundant cultural connotations and a long history are valuable cultural heritage assets. Choronyms not only reflect natural and social phenomena but also help with relevant management and naming work. In order to explore the historical development sequence of choronymic cultural landscape evolution, we analyze the spatial&ndash, temporal pattern evolution, spatial&ndash, temporal variation, spatial association, and semantic evolution of choronymic cultural landscapes since the Qin dynasty. We adopt the sequent snapshot model and an event-based state amendment model to establish a spatio-temporal database. That can provide decision supports and theoretical reference for the sustainable development of toponymic landscapes. Results indicate the following: (1) Spatial distribution of toponym density has been different since the Qin dynasty. The cores of toponym density spread from the middle-lower reaches of the Yellow River to Yangtze Plain, Chengdu Plain, Pearl River Delta Plain. (2) Spatial distribution of choronyms is agglomerative since the Qin dynasty and uneven at national and provincial scales since the Yuan dynasty. Temporal distribution of toponyms at different levels is centralized. (3) Spatial agglomeration phenomena of toponyms are positively clustered in nine periods. The Ming dynasty presents the largest degree of spatial aggregation. (4) Words relevant to blessings, orientation, and hydrological features have high proportions in the top 20 words. (5) Spatial distribution of county-level choronyms named over the last 1000 years and &ldquo, Millennium Ancient Counties&rdquo, are unbalanced at national and provincial scales.

Chronic kidney disease (CKD) is a world-wide public health problem. Hypertension is both a cause and a complication of CKD, and a risk factor for progression of kidney disease. The effect of salt intake on blood pressure (BP) and the salt sensitivity in non-dialysis patients with CKD were studied.One hundred and thirty non-dialysis patients with CKD were enrolled in the present study. Daily urinary excretion of sodium (representative of daily sodium intake) and BP was monitored in conditions of original eating habits. Estimated glomerular filtration rate (eGFR) was measured by the creatinine clearance (Ccr).There was a linear positive relationship between the salt intake and systolic blood pressure (SBP) (β = 0.250, p = 0.004). It had been found that the log of BP/24-h urinary sodium (salt sensitivity index) had linear relationship with the log of eGFR (βsyst = -0.364, p = 0.000, βdiast = -0.345, p = 0.000, respectively). Multi-stepwise regression analysis showed SBP was mainly influenced by salt intake and eGFR. There was a negative correlation between diastolic blood pressure (DBP) and age.These results demonstrated a linear relationship between the salt intake and SBP in non-dialysis patients with CKD. The salt sensitivity of BP rose with the decline of renal function.

A series of 1-ethyl-1′-arylmethyl-4,4′-bipyridinium compounds is synthesized, where the aryl is phenyl (BEV), 2-naphthyl (NEV), 2-anthracenyl (AEV) or 1-pyrenyl (PEV). Among them, PEV and AEV can bind with calf thymus DNA mainly through intercalation and groove-binding modes, and both of them can be observed to photocleave plasmid pBR 322 DNA significantly under irradiation with a xenon arc lamp. After inclusion of cucurbit[8]uril (CB[8]), all of the aromatic donor–viologen acceptor compounds exhibit efficient DNA photocleavage ability. The reason is that CB[8] can inhibit the intramolecular backwards electron transfer in the aromatic donor–viologen acceptor molecule, prolonging the lifetime of the charge separated excited state to some extent. These studies bring a new subject in DNA photocleavage research and a potential application of the host–guest supramolecular system.

N-(4-Hydroxy-phenoxyethyl)-N'-ethyl-4,4'-bipyridium (1) can form a stable 1 : 1 inclusion complex with CB[8] in aqueous solution, in which the hydroxyphenol (HP) moiety is back-folded and inserted together with the viologen moiety into the cavity of CB[8]. When the ethyl viologen dication (EV(2+)) in 1 is reduced, chemically or electrochemically, an intramolecular partner radical (EV(+)*-HP)/CB[8] can be detected, meanwhile, a dynamic balance between the partner radical and the intermolecular radical dimer (EV(+)*-HP)(2)/CB[8] can be observed.