bluuebunny/crossref_metadata_2025_split huggingface dataset:
Application of Travel Service Recommendation Algorithm Based on Cloud Computing
Authors: Arongna  , Sulonggaowa  
Published: April 2021

Abstract
In the context of big data, traditional collaborative filtering recommendation algorithms cannot provide users with accurate recommendation services, making the sparsity of user data become an important factor affecting the accuracy of recommendation in the complex social network environment. This paper mainly studies the design and application of travel service recommendation algorithm based on cloud computing. In this paper, the data is processed based on MapReduce parallel computing framework to improve the performance and speed of the algorithm. The Linux-equipped cluster is deployed under the Hadoop framework. The cluster feasibility test is carried out to realize the recommendation function of the algorithm, and the function of the algorithm is realized according to the actual problems. On the Hadoop big data platform, the traditional algorithm was improved and the hadoop-based collaborative filtering recommendation algorithm was implemented to further improve the recommendation rate and accuracy of the traditional recommendation filtering algorithm.
Characteristics and Trends of Medical-Physical Integration Research-Econometric Analysis Based On CNKI Data (1998-2020)
Authors: Zou Wei , Wang Chao , Luo Yiwen 
Published: April 2021

Abstract
This article uses the visualization software CiteSpace to take the 272 medical-to-physical literatures of China Academic Journals Online Publishing Database (CNKI) as the data source. It attempts to construct knowledge about medical-to-physical integration by quantifying the time of publication, authors, institutions, and keywords. Map and analyze it. The study found that the exploration of medical-physical integration in the context of a healthy China is based on the practice of medical-physical integration. In-depth research is a research hotspot. Based on a comprehensive analysis of the knowledge map of medical-physical integration, the future academic circles on the “medical and physical education reform in various fields and colleges, training professionals” and “improving the masses with sports to promote health concepts, building a healthy China” is likely to become a research hotspot on this topic.
RETRACTED: Countermeasures for Promoting the Development of Sports Economy by Physical Education in Colleges and Universities Based on Big Data Analysis
Authors: Li Nan 
Published: April 2021

Abstract
It can be seen from the successful hosting of the 2008 Olympic Games and the upcoming Winter Olympics in China that my country’s sports economy is on the cusp of rapid development. However, my country’s backward physical education in colleges and universities seriously hinders the development of the sports economy. In order to adapt to the sports economy in my country’s new situation, the reform of college sports education is imminent. To this end, this article mainly injects capital into the reform of physical education in colleges and universities, strengthens teachers through economic strength and complements various competitions, so that my country’s sports economy is steadily on the road of rapid development. In this experiment, the sports economic profit of the experimental group that injected college physical education through the economy was as high as 1.7 million yuan, 8.5 times higher than the control group of traditional physical education. This also confirms that the development of the sports economy first needs to inject capital into sports education, so as to increase people’s consumption of sports activities through education, in order to promote the steady development of my country’s sports economy.
A tunable autocorrelator for pulse measurements at IR FEL-oscillator facilities
Authors: Cicek E. , Seidel W. , Ketenoglu B. 
Published: April 2021

Abstract
Radiation characteristics of a Free-Electron Laser (FEL)
such as pulse length, time structure, intensity, bandwidth,
wavelength, power, frequency, etc., which were measured on a
diagnostics table, are thoroughly discussed. In this respect, pulse
length measurements of an Infrared FEL (IR-FEL) beam are evaluated
through an intensity autocorrelator, designed and installed as a
diagnostics tool at the “Helmholtz-Zentrum Dresden-Rossendorf
(HZDR)-Radiation Source ELBE” of Germany. In addition, the
autocorrelator was designed as a unique, cost-effective, and
in-house setup. It operates within the wavelength range of
3–35 microns, using Cadmium-Telluride (CdTe) crystals in the Second
Harmonic Generation (SHG) medium. The intensity autocorrelation
curves were obtained for the FEL beam with the wavelength of
26.2 microns, indicating an FWHM pulse duration ranging between
3.29–8.03 ps with different optical cavity detuning
values. Furthermore, the pulse duration of Ti: sapphire laser beam
is measured between 1–3 ps through the designed autocorrelator at
the ELBE light source. On the other hand, the setup may pave the way
for pulse length measurements of the Turkish infrared FEL-oscillator
facility (TARLA) as well, which is currently under the hardware
installation phase. Finally, it is elaborated in section 3 that the
unique autocorrelator design fully meets all requirements for pulse
length measurements of an infrared FEL source.
Using social media audience data to analyse the drivers of low-carbon diets
Authors: Eker Sibel , Garcia David , Valin Hugo , van Ruijven Bas 
Published: April 2021

Abstract
Low-carbon lifestyles are key to climate change mitigation, biodiversity conservation, and keeping the Earth in a safe operating space. Understanding the global feasibility and drivers of low-carbon lifestyles requires large scale data covering various countries, demographic and socioeconomic groups. In this study, we use the audience segmentation data from Facebook’s advertising platform to analyse the extent and drivers of interest in sustainable lifestyles, plant-based diets in particular, at a global level. We show that formal education level is the most important factor affecting vegetarianism interest, and it creates a sharper difference in low-income countries. Gender is a strong distinguishing factor, followed by national gross domestic product per capita and age. These findings enable upscaling local empirical studies to a global level with confidence for integrated assessments of low-carbon lifestyles. Future studies can expand this analysis of social media audience data to other consumption areas, such as household energy demand, and can also contribute to quantifying the psychosocial drivers of low-carbon lifestyles, such as personal and social norms.
Application of DRASTIC Entropy Weight Model Method in Groundwater Vulnerability Evaluation in Ordos Area
Authors: Wei Wang , Wenxu Wang , Lin Zhu , Rui Cheng , Lishan Meng , Sheming Chen , Futian Liu 
Published: April 2021

Abstract
The northeastern part of the Ordos Basin is the main recharge area of regional groundwater, the groundwater resources are relatively scarce. The main water supply source in the area is shallow groundwater, and there are many industrial and mining enterprises in the district. The potential groundwater pollution risk is high, and the the shallow groundwater vulnerability evaluation in the region is of great significance for groundwater resources protection.The weight of each indicator of the traditional DRASTIC model is fixed and does not change with the regional conditions, which may cause deviations in the evaluation results. This time, based on the DRASTIC model, the entropy weight coefficient method is introduced to determine the index weight, and the DRASTIC entropy weight model is established to obtain a more scientific and close to the actual conditions of the study area, and provide an important reference and basis for the protection of regional groundwater resources.
An engineered neurovascular unit for modeling neuroinflammation
Authors: Seo Suyeong , Choi Chi-Hoon , Yi Kyung Sik , Kim Seung U , Lee Kangwon , Choi Nakwon , Lee Hong Jun , Cha Sang-Hoon , Kim Hong Nam 
Published: April 2021

Abstract
The neurovascular unit (NVU) comprises multiple types of brain cells, including brain endothelial cells, astrocytes, pericytes, neurons, microglia, and oligodendrocytes. Each cell type contributes to the maintenance of the molecular transport barrier and brain tissue homeostasis. Several disorders and diseases of the central nervous system, including neuroinflammation, Alzheimer’s disease, stroke, and multiple sclerosis, have been associated with dysfunction of the NVU. As a result, there has been increased demand for the development of NVU in vitro models. Here, we present a three-dimensional (3D) immortalized human cell-based NVU model generated by organizing the brain microvasculature in a collagen matrix embedded with six different types of cells that comprise the NVU. By surrounding a perfusable brain endothelium with six types of NVU-composing cells, we demonstrated a significant impact of the 3D co-culture on the maturation of barrier function, which is supported by cytokines secreted from NVU-composing cells. Furthermore, NVU-composing cells alleviated the inflammatory responses induced by lipopolysaccharides. Our human cell-based NVU in vitro model could enable elucidation of both physiological and pathological mechanisms in the human brain and evaluation of safety and efficacy in the context of high-content analysis during the process of drug development.
Gradient rhenium doping enabled tunable anisotropic valleytronic material based on monolayer molybdenum disulfide
Authors: Ma Xinli , Zhang Jing , Lai Jiawei , Zhang Mingwen , Zheng Jingchuan , Wu Sen , Hu Xiaodong , Wang Qinsheng , Gan Xuetao , Sun Dong , Liu Jing 
Published: April 2021

Abstract
Two-dimensional molybdenum disulfide (MoS2) possesses premium electrical, optoelectrical and valleytronic properties to develop future nano-electronic and optoelectronic devices. Valleytronic material platform with anisotropic response is highly desired to develop polarization sensitive valleytronic devices. In this work, we acquire monolayer MoS2 with both valley degree of freedom and anisotropy by introducing Re doping during chemical vapor deposition growth. The atomic substitution with Re element induces prominent n-type doping. Electrical tests under both dark and light illumination show that 5 at% Re-doped MoS2 achieves the optimum electrical and optoelectrical performances, corresponding to 27 and 35 times improved carrier mobility and photoresponsivity than pristine MoS2, respectively. Second harmonic generation (SHG) and polarization Raman spectroscopy (PRS) indicate increased anisotropic optical response of Re doped MoS2 as Re concentration increases: maximum anisotropic ratios of 1.6 and 1.7 have been achieved for SHG and PRS measurements at different doping concentrations, respectively. Circularly polarized PL measurement demonstrates that the Re-doped MoS2 preserves valley dependent optical response. Our theoretical calculations show that the anisotropic response is due to the strain induced by the dopants, so that the 2H lattice structure optical helicity dependent valley selection rules are largely preserved. The work opens promising venue toward polarization sensitive valleytronic material platform.
Fatigue property and failure mechanism of TC4 titanium alloy in the HCF and VHCF region considering different forging processes
Authors: Cui Wenbin , Chen Xuan , Cheng Li , Ding Junliang , Wang Changkai , Wang Bohan 
Published: April 2021

Abstract
Based on the self-built three point bending ultrasonic fatigue test system, fatigue behavior of TC4 titanium alloy after different forging processes in high cycle fatigue (HCF) and very high cycle fatigue (VHCF) regimes was discussed in this paper. The experimental results showed that the fatigue S-N curves of TC4 titanium alloy with three different structures presented different characteristics: continuous decline; double platform; linear decline. The fatigue property of TC4 titanium alloy is closely related to the content of primary α phase and β-transformed microstructure. For TC4 titanium alloy, grain refinement and certain volume fraction of the primary α phase contributed to enhancing fatigue property. The fatigue performance of bimodal structure by near β forging was obviously better than two structures by α + β forging in HCF and VHCF regime. It was found that failure mode shifted from the surface at relatively high stress to the subsurface at relatively low stress. For three kinds of structures, crack initiations were observed at the surfaces of specimens in HCF regime. Meanwhile, cracks of the three structures all originated from primary α cleavage planes in the interior. The fatigue life of VHCF is dominated by the crack initiation stage.
Field emission characteristics of a nanotube-fullerene composite: a theoretical study
Authors: Xu Shunfu , Feng Huaiwei , Zhang Yuming , Liu Weihui , Li Chun , Yuan Guang 
Published: April 2021

Abstract
First-principles calculations are used to investigate electronic and field emission characteristics of a nanotube-fullerene composite (a single-walled carbon nanotube (CNT) with a C20 molecule), which indicate that emission currents of the CNT-fullerene composite under external electric fields are roughly four times higher than those of original carbon nanotubes, and its pentagon on the apex is the highest probable positions for electron emission. Moreover, work functions of the CNT-fullerene composite decrease linearly with applied electric fields. The remarkable influence of lithium adsorption on electronic and field emission characteristics of the CNT-fullerene composite is also investigated. After lithium adsorption, the work functions of the CNT-fullerene composite decline evidently, while the emission currents increase polynomially. The emission currents of the adsorption system have been improved by two orders of magnitude (with an order of 10−4 A), and the lithium adatom above on the apex is the most probable position for emission.
Investigation of melt-growth alumina/aluminum titanate composite ceramics prepared by directed energy deposition
Authors: Huang Yunfei , Wu Dongjiang , Zhao Dake , Niu Fangyong , Ma Guangyi 
Published: April 2021

Abstract
Al2O3/Al6Ti2O13 composite ceramics with low thermal expansion properties are promising for the rapid preparation of large-scale and complex components by directed energy deposition-laser based (DED-LB) technology. However, the wider application of DED-LB technology is limited due to the inadequate understanding of process conditions. The shaping quality, microstructure, and mechanical properties of Al2O3/Al6Ti2O13 (6 mol% TiO2) composite ceramics were systematically investigated as a function of energy input in an extensive process window. On this basis, the formation mechanism of solidification defects and the evolution process of microstructure were revealed, and the optimized process parameters were determined. Results show that high energy input improves the fluidity of the molten pool and promotes the uniform distribution and full growth of constituent phases, thus, facilitating the elimination of solidification defects, such as pores and strip gaps. In addition, the microstructure size is strongly dependent on the energy input, increasing when the energy input increases. Moreover, the morphology of the α-Al2O3 phase gradually transforms from cellular into cellular dendrite with increasing energy input due to changing solidification conditions. Under the comprehensive influence of solidification defects and microstructure size, the fracture toughness and flexural strength of Al2O3/Al6Ti2O13 composite ceramics present a parabolic law behavior as the energy input increases. Optimal shaping quality and excellent mechanical properties are achieved at an energy input range of 0.36−0.54 W*min2 g−1 mm−1. Within this process window, the average microhardness, fracture toughness, and flexural strength of Al2O3/Al6Ti2O13 composite ceramics are up to 1640 Hv, 3.87 MPa m1/2, and 227 MPa, respectively. This study provides practical guidance for determining the process parameters of DED-LB of melt growth Al2O3/Al6Ti2O13 composite ceramics.
Chronic Blockade of NMDAR Subunit 2A in the Hypothalamic Paraventricular Nucleus Alleviates Hypertension Through Suppression of MEK/ERK/CREB Pathway
Authors: Li Ying , Lu Yu-Xin , Chi Hong-Li , Xiao Tong , Chen Yan-Mei , Fu Li-Yan , Zibrila Abdoulaye Issotina , Qi Jie , Li Hong-Bao , Su Qing , Gao Hong-Li , Zhang Yan , Shi Xiao-Lian , Yu Xiao-Jing , Kang Yu-Ming 
Published: April 2021

Abstract

BACKGROUND
N-Methyl-d-aspartate receptor (NMDAR) in the hypothalamic paraventricular nucleus (PVN) plays critical roles in regulating sympathetic outflow. Studies showed that acute application of the antagonists of NMDAR or its subunits would reduce sympathetic nerve discharges. However, little is known about the effect of long-term management of NMDAR in hypertensive animals.

METHODS
PEAQX, the specific antagonist of NMDAR subunit 2A (GluN2A) was injected into both sides of the PVN of two-kidney, one-clip (2K1C) renal hypertensive rats and control (normotensive rats) for 3 weeks.

RESULTS
Three weeks of PEAQX infusion significantly reduced the blood pressure of the 2K1C rats. It managed to resume the balance between excitatory and inhibitory neural transmitters, reduce the level of proinflammatory cytokines and reactive oxygen species in the PVN, and reduce the level of norepinephrine in plasma of the 2K1C rats. PEAQX administration also largely reduced the transcription and translation levels of GluN2A and changed the expression levels of NMDAR subunits 1 and 2B (GluN1 and GluN2B). In addition, NMDAR was known to function through activating the extracellular regulated protein kinases (ERK) or phosphatidylinositol 3-kinase/protein kinase B (PI3K/Akt) pathways. In our study, we found that in the PVN of 2K1C rats treated with PEAQX, the phosphorylation levels of mitogen-activated protein kinase kinase (MEK), ERK1/2, and cAMP-response element-binding protein (CREB) significantly reduced, while the phosphorylation level of PI3K did not change significantly.

CONCLUSIONS
Chronic blockade of GluN2A alleviates hypertension through suppression of MEK/ERK/CREB pathway.
Antihypertensive prescribing patterns and hypertension control in females of childbearing age
Authors: White Blaire M , Anderson Sarah L , Marrs Joel C 
Published: April 2021

Abstract

Purpose
The use of angiotensin-converting enzyme (ACE) inhibitors or angiotensin receptor blockers (ARBs) to treat hypertension (HTN) during pregnancy presents well-established risks to a developing fetus. A cross-sectional study was conducted to evaluate the current state of antihypertensive prescribing and contraceptive use in females of childbearing age within a large safety-net health system.

Methods
The retrospective cross-sectional study focused on females aged 18-49 years with a documented diagnosis of HTN. The proportion of patients prescribed an ACE inhibitor or ARB and using a documented form of contraception was calculated. Documented forms of contraception included oral contraceptives, intrauterine devices, injections, implants, and surgical intervention.

Results
A total of 4,187 patients were identified from the HTN registry; after application of exclusion criteria 3,045 patients were included in the study population. The mean age was 39 years (range, 18-49 years). The most frequently prescribed classes of antihypertensive medications were ACE inhibitors and ARBs (one or the other was used by 1,146 patients [37.6%]), followed by thiazide diuretics (n = 710, 23.3%) and calcium channel blockers (n = 599, 19.7%). Of the 1,146 patients prescribed an ACE inhibitor or ARB, 553 (48%) were using a documented form of contraception.

Conclusion
Rates of ACE inhibitor or ARB prescribing to females of childbearing age were high despite the teratogenic risks, and fewer than half of patients had documented protection from pregnancy. Provider and patient education and potential creation of best practice alerts in the electronic medical record regarding the risks of using ACE inhibitors and ARBs in females of childbearing age are warranted.
Alpine speciation and morphological innovations: revelations from a species-rich genus in the northern hemisphere
Authors: Zhang Yazhou , Chen Jianguo , Sun Hang 
Published: April 2021

AbstractA large number of studies have attempted to determine the mechanisms driving plant diversity and distribution on a global scale, but the diverse and endemic alpine herbs found in harsh environments, showing adaptive evolution, require more studies. Here, we selected 466 species from the genus Saussurea, one of the northern hemisphere’s highest-altitude plant genera with high species richness and striking morphological traits, to explore the mechanisms driving speciation and adaptative evolution. We conducted phylogenetic signals analysis and ancestral character estimation to explore the phylogenetic significance of ecological factors. Moreover, we used spatial simultaneous autoregressive (SAR) error models, modified t-tests and partial regression models to quantify the relative effects of ecological factors and morphological diversity upon diversity and endemism of Saussurea. Phylogenetic analyses reveal that geological influences and climate stability exhibit significant phylogenetic signals and that Saussurea originated at a relatively high elevation. Regression models indicate that geological influences and climatic stability significantly affect the diversity and endemism patterns of Saussurea and its morphological innovations. Moreover, morphological innovations in an area show significant contributions to the local diversity and endemism of Saussurea. We conclude that geological influences (mean altitude and topographic heterogeneity), glacial–interglacial climate stability and phylogenetic conservatism have together promoted the speciation and adaptive evolution of the genus Saussurea. In addition, adaptively morphological innovations of alpine species also promote diversification in local regions. Our findings improve the understanding of the distribution pattern of diversity/endemism and adaptive evolution of alpine specie in the whole northern hemisphere.