472 research outputs found
7-(3-Nitrophenyl)-9,10-dihydro-7H-benzo[h]cyclopenta[b]quinolin-8(11H)-one
In the title compound, C22H16N2O3, the naphthalene ring, the 1,4-dihydropyridine ring and the cyclopent-2-enone ring are nearly coplanar, with the dihedral angles between the neighbouring rings being 1.93 (11) and 2.30 (9)°, respectively. The benzene ring group at position 7 and the 1,4-dihydropyridine ring form a dihedral angle of 78.75 (4)°. Intermolecular N—H⋯O hydrogen bonds and C—H⋯π interactions stabilize the crystal packing
Research and implementation of parallel artificial bee colony algorithm based on ternary optical computer
The artificial bee colony (ABC) algorithm is a widely used algorithm in the field of function optimization problems. The traditional ABC algorithm has long search time, slow convergence speed and easy to fall into local optimum at the end of the search. In this paper, the design scheme and method of implementing parallel ABC algorithm are studied, which makes use of the characteristics of many data bits and easy expansion of data bits of the ternary optical computer (TOC). First, by analysing the traditional ABC algorithm, we can find the parallel parts and parallel design. Then the detailed algorithm implementation flow is given and the clock cycle of the algorithm is analysed. Finally, the correctness of the parallel scheme is verified by experiments. Compared with the ABC algorithm and parallel ABC algorithms based on computer (PABC), the ABC algorithm based on TOC (TOC-PABC) effectively shortens the search time, improves the optimization performance of complex multimodal function optimization problems and obtains a higher speedup
4-(4-Bromophenyl)-3-methyl-1-phenyl-6,7-dihydro-1H-pyrazolo[3,4-b]thieno[2,3-e]pyridine 5,5-dioxide
In the title compound, C21H16BrN3O2S, the pyrazole and pyridine rings are nearly coplanar, the dihedral angle between their planes being 3.17 (14)°. The 2,3-dihydrothiophene ring adopts an envelope conformation. The 4-bromophenyl/pyridine ring and phenyl/pyrazole rings form dihedral angles of 60.06 (9) and 33.49 (11)°, respectively. There is an intramolecular C—H⋯N hydrogen bond. The crystal packing is stabilized by intermolecular C—H⋯O hydrogen bonding and C—H⋯π interactions
Condom use consistency and associated factors among college student men who have sex with men from seven colleges in Changsha city : a cross-sectional survey
Background: College student men who have sex with men (MSM) are at high risk for HIV infection due to multiple social and behavioral factors. Consistent condom use is nationally advocated for HIV prevention. This study explored the sexual behaviors and factors associated with condom use consistency in the past six months among college student MSM from seven colleges in Hunan Province, China. Methods: A cross-sectional survey was conducted from September 2017 to March 2018. Condom use consistency, sexual behaviors, HIV testing performance, substance use, and alcohol consumption were examined using researcher-created questionnaires. Condom use self-efficacy and HIV-related knowledge were assessed using the Condom Use Self-Efficacy Scale and the unified National AIDS Sentinel Surveillance Questionnaire. Univariate and multivariate logistic regressions were used. P <0.05 was considered significant. Results: In the 214 respondents, the rate of consistent condom use was 56% (n = 119) during the past six months. Participants who were studying at first-tier universities (odds ratio [OR]: 2.522, 95% confidence interval [CI]: 1.255–5.067) and had higher scores for condom use self-efficacy (OR: 2.617, 95% CI: 1.462–4.685) were more likely to report consistent condom use than the others. The risk factor was having suspicious symptoms of sexually transmitted diseases (OR: 0.357, 95% CI: 0.163–0.780). Conclusion: Numerous students were at high risk of HIV infection with inconsistent condom use. Comprehensive and specific topics about safe sex education from parents and peers should be offered on campuses in China. © 2021 Wang et al
Presence of CP4-EPSPS Component in Roundup Ready Soybean-Derived Food Products
With the widespread use of Roundup Ready soya (event 40-3-2) (RRS), the traceability of transgenic components, especially protein residues, in different soya-related foodstuffs has become an important issue. In this report, transgenic components in commercial soya (including RRS) protein concentrates were firstly detected by using polymerase chain reaction (PCR) and western blot. The results illustrated the different degradation patterns of the cp4-epsps gene and corresponding protein in RRS-derived protein concentrates. Furthermore, western blot was applied to investigate the single factor of food processing and the matrix on the disintegration of CP4-EPSPS protein in RRS powder and soya-derived foodstuffs, and trace the degradation patterns during the food production chain. Our results suggested that the exogenous full length of CP4-EPSPS protein in RRS powder was distinctively sensitive to various heat treatments, including heat, microwave and autoclave (especially), and only one degradation fragment (23.4 kD) of CP4-EPSPS protein was apparently observed when autoclaving was applied. By tracing the protein degradation during RRS-related products, including tofu, tou-kan, and bean curd sheets, however, four degradation fragments (42.9, 38.2, 32.2 and 23.4 kD) were displayed, suggesting that both boiling and bittern adding procedures might have extensive effects on CP4-EPSPS protein degradation. Our results thus confirmed that the distinctive residues of the CP4-EPSPS component could be traced in RRS-related foodstuffs
Willingness, preferred ways and potential barriers to use pre-exposure prophylaxis for HIV prevention among men who have sex with men in China
Objective
To explore willingness and preferred ways to use HIV pre-exposure prophylaxis (PrEP), factors associated with willingness, and potential barriers to PrEP use among men who have sex with men (MSM) in Changsha, China.
Design
A cross-sectional survey was conducted from 25 June to 31 August 2019. Two hundred and fifty-five MSM were recruited from three community-based organisations (CBOs) in Changsha City. Willingness and potential barriers to use PrEP were examined using researcher-created scales. Univariate and multivariate logistic regression was used to analyse the factors associated with willingness to use PrEP. P values <0.05 were considered significant.
Setting
Three MSM inclusive CBOs in Changsha, Hunan Province, China.
Participants
255 HIV-negative MSM were recruited through their CBOs with snowball sampling.
Results
Less than half of the participants (43.1%) had heard of PrEP and 15.3% were willing to use PrEP. The participants reported higher willingness to use event-driven PrEP (3.70±0.07) than daily PrEP (2.65±0.07). Higher self-rated risk and fear of contracting HIV (OR: 14.47, 95% CI 2.19 to 95.53), awareness of PrEP (OR: 4.20, 95% CI 1.64 to 10.73), sharing one’s own sexual orientation with parents or siblings (OR: 2.52, 95% CI 1.54 to 7.20) and having a university education or above (OR:0.29, 95% CI 0.12 to 0.72) were associated with willingness to use PrEP. Only 12.2% of the sample was concerned about potential barriers to PrEP use.
Conclusion
Efforts to improve awareness and knowledge of PrEP, teach self-evaluation of HIV infection risk and provide social and emotional support for MSM are needed to scale up PrEP implementation in China
Topology and evolution of international trade network for fish and fish products
In this study, a complex network method was employed to quantify the changing role of countries in fish trade and the dynamic characteristics of fish globalization. Based on the United Nations Comtrade Database, the International Trade Network for Fish and Fish Products (ITN-Fish) was constructed as a series of weighted-directed networks for each year from 1990 to 2018. Almost all countries and territories worldwide have participated in the fish trade. In 2018, the network identified 229 fish traders. The share of developing countries in imports and exports has increased. Traders actively establish new trade relations, which improve network connectivity. However, these relations only account for a small part of the fish trade. The high connectivity allows risks to spread rapidly in the world through hubs such as the United States and China, which raises concerns about the robustness of these weak links in the Sino-US trade conflict and the outbreak of COVID-19. However, we have optimistic expectations on this issue. The dynamic of network topology property shows that the globalization of fish trade flourished between 1990 and 2018. Although, due to the financial crisis and its subsequent impact, the total amount of fish trade declined in 2009 and 2015, the network structure was not seriously affected, and the trend of topology property remained unchanged. Based on the construction of the international trade network, its node attribute, and its structural attribute, fish trade maintains the trend of globalization. Countries should actively adhere to trade globalization to promote the development of the fish trade
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