A model of the Sb2Se3 solar cell with a hole transport layer (HTL) has been investigated by solar cell capacitance simulator (SCAPS). The influence of different HTLs on device performance has been ...firstly analyzed, and CuO has been found to be the best HTL. Then, Sb2Se3 thickness, CuO thickness, the doping concentration of CuO, the hole mobility of CuO, the defect density of Sb2Se3 layer, the defect density at the CdS/Sb2Se3 interface, and the work function of metal electrode on device performance have been systematically studied. The optimum thicknesses of Sb2Se3 and CuO are 300 nm and 20 nm, respectively. To achieve ideal performance, the doping concentration of CuO should be more than 1019 cm−3, and its hole mobility should be over 1 cm2V−1 s−1. The defect densities in the Sb2Se3 layer and at the CdS/ Sb2Se3 interface play a critical role on device performance, both of which should be as low as 1013 cm−3 and 1014 cm−2, respectively. In addition, the work function of the metal electrode should be more than 4.8 eV to avoid formation of Schottky junction at the metal electrode interface. After optimization, a best efficiency of 23.18% can be achieved. Our simulation results provide valuable information to further improve the efficiency of Sb2Se3 solar cells in practice.
Si3N4 ceramic as a tool material shows promising application prospects in high-speed machining fields; however, the required high mechanical properties and low-cost preparation of Si3N4 ceramic tool ...materials restrict its application. Herein, synergistic reinforced Si3N4 ceramic tool materials were fabricated by adding β-Si3N4 seeds, inexpensive Si3N4 whiskers and TiC particles into coarse commercial Si3N4 powder (D50 = 1.5 μm), then sintering by hot-pressing with low temperature and short holding time (1600 °C—30 min—40 MPa). The phase assemblage, microstructure evolution and toughening mechanisms were investigated. The results reveal that the sintered Si3N4 ceramics with synergistic reinforcement, compared to those with individual reinforcement, present an enhancement in relative density (from 94.92% to 97.15%), flexural strength (from 467.56 ± 36.48 to 809.10 ± 45.59 MPa), and fracture toughness (from 8.38 ± 0.19 to 10.67 ± 0.16 MPa·m1/2), as well as a fine Vickers hardness of 16.86 ± 0.19 GPa. Additionally, the various reinforcement modes of Si3N4 ceramics including intergranular fracture, crack deflection, crack bridging and whiskers extraction were observed in crack propagation, arising from the contributions of the added β-Si3N4 seeds, Si3N4 whiskers and TiC particles. This work is expected to serve as a reference for the production of ceramic cutting tools.
Electroacupuncture has been widely used to treat cognitive impairment after cerebral ischemia, but the underlying mechanism has not yet been fully elucidated. Studies have shown that autophagy plays ...an important role in the formation and development of cognitive impairment, and the phosphoinositide 3-kinase (PI3K)/Akt signaling pathway plays an important role in autophagy regulation. To investigate the role played by the PI3K/Akt signaling pathway in the electroacupuncture treatment of cerebral ischemia/reperfusion rat models, we first established a rat model of cerebral ischemia/reperfusion through the occlusion of the middle cerebral artery using the suture method. Starting at 2 hours after modeling, electroacupuncture was delivered at the Shenting (GV24) and Baihui (GV20) acupoints, with a dilatational wave (1-20 Hz frequency, 2 mA intensity, 6 V peak voltage), for 30 minutes/day over 8 consecutive days. Our results showed that electroacupuncture reduced the infarct volume in a rat model of cerebral ischemia/reperfusion injury, increased the mRNA expression levels of the PI3K/Akt signaling pathway-related factors Beclin-1, mammalian target of rapamycin (mTOR), and PI3K, increased the protein expression levels of phosphorylated Akt, Beclin-1, PI3K, and mTOR in the ischemic cerebral cortex, and simultaneously reduced p53 mRNA and protein expression levels. In the Morris water maze test, the latency to find the hidden platform was significantly shortened among rats subjected to electroacupuncture stimulation compared with rats without electroacupuncture stimulation. In the spatial probe test, the number of times that a rat crossed the target quadrant was increased in rats subjected to electroacupuncture stimulation compared with rats without electroacupuncture stimulation. Electroacupuncture stimulation applied to the Shenting (GV24) and Baihui (GV20) acupoints activated the PI3K/Akt signaling pathway and improved rat learning and memory impairment. This study was approved by the Animal Ethics Committee of the First Affiliated Hospital of Henan University of Traditional Chinese Medicine, China (approval No. 8150150901) on March 10, 2016.
Recently, an increasing number of studies have focused on the extra-gastrointestinal effects of Helicobacter pylori (H. pylori), including metabolic syndrome, fatty liver, and rheumatic and skin ...diseases. Osteoporosis is an asymptomatic disease that can eventually lead to fractures and has a significant impact on the quality of life of elderly individuals. Sex is an influential factor that plays a crucial role in the development of osteoporosis. The aim of this study was to investigate the relationship between H. pylori infection and osteoporosis and to identify potential influencing factors.
We conducted a cross-sectional study of individuals older than 50 years old, who had undergone regular physical examinations at the Beijing Shijitan Hospital Health Examination Center from July to October 2018. We evaluated the associations of osteopenia and osteoporosis with H. pylori infection and related serum markers by using multiple linear regression and logistic regression. Then, we analysed the correlation between sex and potential serum biomarkers.
There were significant relationships between H. pylori infection status and bone density in premenopausal females but not in males (P = 0.381) according to Fisher's exact test. In females, H. pylori positivity (OR = 0.132, P = 0.023), Body Mass Index (BMI) (OR = 28.163, P = 0.021), and homocysteine (HCY) (OR = 17.218, P = 0.045) were associated with osteoporosis. Calcium had a trend but no statistically significant (OR = 0.060, P = 0.076) relationship with osteoporosis. Furthermore, the waist-to-hip ratio (OR = 5.783, P = 0.029), BMI (OR = 0.152, P = 0.014) and triglyceride levels (OR = 0.201, P = 0.036) were significantly different by sex, after adjusting for age as a confounder.
H. pylori positivity, BMI and HCY are associated with osteoporosis in premenopausal females. Chronic inflammation may be involved in the relationship between H. pylori and osteoporosis.
The Linnan subsag is a petroliferous, secondary tectonic unit of the Huimin sag that is located in the western part of the Jiyang depression in the Bohai Bay basin, eastern China. In this study, the ...authors calculated basin extensional rate and slipping displacement of boundary faults in the dip and strike directions, using seismic and drilling data. The evolution of the Linnan transtensional basin from the Eogene through the Quaternary is quantitatively described, and a dynamic model is established. The Linshan and Xiakou boundary faults of the Linnan subsag are used as a case study to describe a method to calculate the strike and dip slipping displacements of active faults under oblique extension. The results quantitatively illustrate the behavior of the Linnan subsag boundary faults over time. The Linnan subsag transtensional basin experienced four stages of evolution: weak extension during the Kongdian Formation, rapid extension and fault depression during the fourth member of the Shahejie Formation, intensive transtension and fault depression during the third member of the Shahejie Formation–Dongying Formation, and weakening fault depression during the Guantao Formation–Pingyuan Formation. The results of this study provide further understanding of the processes of petroleum migration and accumulation in the region.
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•The Linnan subsag is a typical transtensional basin.•Presenting a method to calculate the slipping displacement of transtensional fault.•Calculating the slipping displacement of boundary faults.•Calculating the basin extension rate of Linnan subsag.•Quantitatively describing the transtensional structure evolution of the Linnan subsag.
Fan‐beam antenna design based on metasurface lenses Wang, He; Dong, Xiao‐Feng; Shen, Jian ...
International journal of RF and microwave computer-aided engineering,
April 2021, 2021-04-00, 20210401, Letnik:
31, Številka:
4
Journal Article
Recenzirano
Odprti dostop
A fan‐beam antenna system based on metasurface lenses is proposed for backhaul antenna applications at 10.4 GHz. The planar metasurface lens is composed of three pairs of subwavelength unit cells ...with high transmission and opposite phase. These phase shifters are arranged to transform the Gaussian distributed near field from a linear patch antenna array into the sin c‐function distributed aperture field, which in turn brings a sector radiation pattern in the azimuth plane and a pencil beam in the elevation plane. The simulated and measured results demonstrate that the presented lens antenna offers a sharp roll‐off fan beam with the azimuth beamwidth 60°, elevation beamwidth 10°, and the gain 18.2 dB with the flat‐top ripple less than 2.0 dB.
The mass spectrometry based technical pipeline has provided a high-throughput, high-sensitivity and high-resolution platform for post-genomic biology. Varied models and algorithms are implemented by ...different tools to improve proteomics data analysis. The target-decoy searching strategy has become the most popular strategy to control false identification in peptide and protein identifications. While this strategy can estimate the false discovery rate (FDR) within a dataset, it cannot directly evaluate the false positive matches in target identifications.
As a supplement to target-decoy strategy, the entrapment sequence method was introduced to assess the key steps of mass spectrometry data analysis process, database search engines and quality control methods. Using the entrapment sequences as the standard, we evaluated five database search engines for both the origanal scores and reprocessed scores, as well as four quality control methods in term of quantity and quality aspects. Our results showed that the latest developed search engine MS-GF+ and percolator-embeded quality control method PepDistiller performed best in all tools respectively. Combined with efficient quality control methods, the search engines can improve the low sensitivity of their original scores. Moreover, based on the entrapment sequence method, we proved that filtering the identifications separately could increase the number of identified peptides while improving the confidence level.
In this study, we have proved that the entrapment sequence method could be an useful strategy to assess the key steps of the mass spectrometry data analysis process. Its applications can be extended to all steps of the common workflow, such as the protein assembling methods and data integration methods.
Cognitive impairment is a common dysfunction after stroke that seriously affects the overall recovery of patients. Cognitive rehabilitation training is currently the main treatment to improve ...cognitive function, but its curative effect is limited. Acupuncture is a core component of traditional Chinese medicine (TCM), and some previous clinical studies have shown that it might be effective in treating post-stroke cognitive impairment (PSCI), but further evidence from large-sample studies is needed. The overall objective of this trial is to obtain further data to develop an optimized acupuncture treatment for PSCI by comparing the effects of different acupuncture treatment methods on cognitive function in PSCI patients.
In this multicenter, prospective, randomized controlled trial, 206 eligible stroke inpatients who meet the trial criteria will be randomly assigned to 2 groups: an electroacupuncture (EA) plus needle retention (NR) group and an EA group. Both groups of patients will undergo the same routine cognitive rehabilitation treatments. All treatments will be given 5 times per week for 8 weeks. The primary outcomes will be assessed using the Mini-Mental State Examination (MMSE) and the Montreal Cognitive Assessment scale (MOCA). The secondary outcome will be measured by the Barthel Index (BI). All outcomes will be evaluated at baseline, week 4, week 8, and the third and sixth month after the end of treatment.
Our aim is to evaluate the effects of two different acupuncture treatment methods for treating PSCI patients. This study is expected to provide data to be used in developing an optimized acupuncture treatment method for PSCI treatment.
Chinese Clinical Trial Registry ChiCTR1900027849. Registered on 30 November 2019, http://www.chictr.org.cn/showproj.aspx?proj=46316.
Objectives
Acupuncture therapy has been used for cognitive impairment-related diseases, however, there are still few studies on the overall trend of acupuncture therapy on cognitive impairment based ...on bibliometric analysis. The purpose of this study was to explore the research trend of the impact of acupuncture on cognitive impairment in the past 15 years, analyze the research trends and hotspots, and provide new ideas and theoretical basis for future research directions.
Methods
From the Web of Science Core Collection (WoSCC), the relevant literature on the treatment of cognitive impairment with acupuncture from 2007 to 2022 was retrieved. Then, based on the CiteSpace and VOSviewer software of the Java platform, the cooperation between countries and institutions in this field, the co-citation of journals and documents, and the cooperation between authors and authors, etc. were analyzed. In addition, the co-occurrence and burst analysis of keywords are also carried out, and a visual knowledge map is drawn.
Results
As of August 08, 2022, a total of 394 records related to the treatment of cognitive impairment with acupuncture were identified. The analysis results show: The number and rate of annual publications have steadily increased, with some fluctuations from year to year. The countries that contribute the most to this field are China and the USA. Among them, Beijing University of Chinese Medicine and Capital Medical University are tied for first place in terms of the number of published papers. Tao Jing is the most prolific author and the number one cited author.
Conclusions
The number of publications on acupuncture for cognitive impairment is expected to increase rapidly in future research, suggesting a bright future for the field. Future research hotspots will focus on pain, injury, protocol, diagnosis, guidelines, etc. It is also necessary to strengthen cross-regional and cross-country cooperation among various academic groups.
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