63 research outputs found
Identification of a sub-micromolar, non-peptide inhibitor of β-secretase with low neural cytotoxicity through in silico screening
Nowadays identification of novel non-peptide β-secretase (BACE-1, hereinafter) inhibitors with low cytotoxicity and good bloodâbrain barrier (BBB) property holds common interest of drug discovery for Alzheimerâs disease. Twenty SPECS compounds were tested in BACE-1 FRET assays and methylthiazoletetrazolium (MTT) cytotoxicity experiment. Two compounds: 2 and 15 demonstrated IC50 values of 0.53 and 9.4 ÎźM. In addition, 2 showed least toxic effect to the neuroblastoma cells. The results from both in silico and in vitro studies provided new pharmacophoric entities for chemical synthesis and optimization on the current discovered BACE-1 small molecule inhibitors
Molecular docking and structure-activity relationship studies on benzothiazole based non-peptidic BACE-1 inhibitors
A similarity search on the structural analogs of an inhibitor of BACE-1 with IC50 2.8 ΟM, which contained a P1 benzothiazole group together with a triazine ring linked by a secondary amine group, was described in this Letter and some more potent inhibitors against BACE-1 were identified. The most potent compound 5 (IC50 = 0.12 ΟM) increases the inhibitory potency by 24 folds. Our results suggest that a pyrrolidinyl side group at the P3Ⲡand P4Ⲡof the inhibitors are favored for strong inhibition and a small aromatic group at the P4 position is also essential to the potency
3D-QSAR studies of checkpoint kinase 1 inhibitors based on molecular docking and CoMFA
Three-dimensional quantitative structureâactivity relationship (3D-QSAR) studies were performed on a series of substituted 1,4-dihydroindeno[1,2-c]pyrazoles inhibitors, using molecular docking and comparative molecular field analysis (CoMFA). The docking results from GOLD 3.0.1 provide a reliable conformational alignment scheme for the 3D-QSAR model. Based on the docking conformations and alignments, highly predictive CoMFA model was built with cross-validated q 2 value of 0.534 and non-cross-validated partial least-squares analysis with the optimum components of six showed a conventional r 2 value of 0.911. The predictive ability of this model was validated by the testing set with a conventional r 2 value of 0.812. Based on the docking and CoMFA, we have identified some key features of the 1,4-dihydroindeno[1,2-c]pyrazoles derivatives that are responsible for checkpoint kinase 1 inhibitory activity. The analyses may be used to design more potent 1,4-dihydroindeno[1,2-c]pyrazoles derivatives and predict their activity prior to synthesis
Evolution and vulnerability analysis of the global trade pattern in the lithium industry chain
[Objective] This study aims to simulate the vulnerability of the lithium industry trade network in the event of interruption risks. The goal is to effectively identify key nodes and potential risks in the network, providing decision support for optimizing trade patterns and avoiding interruption risks. [Methods] Analyzing the evolution of the lithium industry trade pattern based on trade flow methods, intentional attack simulations were conducted to assess the vulnerability of the lithium industry trade network after trade interruptions occurred in the top 10% of nodes by PageRank centrality. [Results] The research reveals: (1) The global trade pattern of the lithium industry chain is undergoing profound restructuring and transformation, with Chinaâs position highlighted in the global trade network. (2) Invulnerability in the upstream network of the lithium industry chain has improved during the sample period, while the risk resistance capabilities of the midstream and downstream networks are relatively stable. (3) The vulnerability ranking of the lithium industry chain is downstream < midstream < upstream. When trade interruptions occur in the top 10% of global key nodes, the overall performance of the upstream, midstream, and downstream trade networks decreases by an average of 60%, 35%, and 23.5%, respectively. [Conclusion] To maintain the security and stability of Chinaâs and the global lithium industry, the following measures should be implemented: enhance and refine safety risk warning and emergency support mechanisms within the lithium industry chain; establish a cooperative, win-win framework among key stakeholders in the lithium industry chain to bolster positive response capabilities across the industry, supply chain, and value chain; and improve domestic self-sufficiency and global allocation capabilities for lithium resources
Impact of a water-sediment regulation scheme on nutrient variations at the Lijin station of the Yellow River
The water-sediment regulation scheme (WSRS) imposed on dams throughout the Yellow River not only alleviates siltation in the downstream section but also alters the nutrient characteristics, which indirectly affects the enrichment of nutrients in the estuary. Nevertheless, the long-term changes in the nutrient contents and their causes in the lower Yellow River (LYR) remain unclear, and the nutrients characteristics during the years with and without WSRS have yet to be compared. Therefore, the purpose of this study was to explore the variations in the nutrient contents and limitations at the Lijin station on the LYR over the past decade, especially during the annual WSRS period, and to compare the water quality characteristics at Lijin between the years with and without WSRS. The results reveal that WSRS significantly changed the seasonal nutrient concentrations (nitrogen, phosphorus and silicon) at the Lijin station. The fluxes of these nutrients during WSRS (excluding 2016 and 2017) accounted for 11.64â40.63% of the total annual fluxes. The N concentration in the LYR was higher than that in some global rivers, while the concentrations of dissolved inorganic phosphorus (DIP) and dissolved silica (DSi) were lower than the average levels in other rivers. In addition, higher values of dissolved inorganic nitrogen (DIN), DSi and the Redfield ratio indicated that the growth of phytoplankton at the Lijin station was strongly restricted by P. However, during the 2Â years without WSRS (2016 and 2017), the proportions of the nutrient fluxes in June were less than 66% of those in the WSRS period in other years. Additionally, there was a potential Si limitation in June in these 2Â years. Furthermore, due to the occurrence of floods upstream of the Yellow River and the low-level operation of the Xiaolangdi Reservoir, the fluxes of nutrients during WSRS in 2018 were approximately 0.90â4.20 times those during the same period in 2009â2015 and 6.30â35.76 times those in June 2016 and June 2017. This study shows that WSRS effectively changes the nutrient balance in the LYR and provides a reference for the multi-objective collaborative optimization of WSRS to improve siltation and control flood in the LYR
An LSTM-STRIPAT model analysis of Chinaâs 2030 CO2 emissions peak
To achieve Chinaâs CO2 emissions targets, all Chinese provinces need to ensure that their CO2 emissions are maintained at a reasonable level to avoid the shortboard effect. This paper proposed an integrated method, the LSTM-STIRPAT, to predict the CO2 emissions in 30 provinces, and assess the drivers of a different region. We divide 30 provinces according to the prediction result into provinces with peak value(PWP) and provinces without peak value(PWTP) and found that (i) Inner Mongolia, Jiangxi, Shandong, Hainan, Chongqing, Guizhou, Qinghai, Xinjiang are failed to reach their CO2 emissions peak by 2030, but almost all provinces experienced a small peak in their carbon emissions from 2008 to 2013; (ii) The ranking of CO2 emissions influencing factors in the PWTP is energy intensity (+) > population density (+) > energy consumption (+) > urbanization rate (â) > GDP per capita (+) > ratio of secondary industry (+); the ranking of CO2 emissions influencing factors in the PWP is energy intensity (+) > ratio of secondary industry (+) > urbanization rate (â) > population density (+) > energy consumption (+) > GDP per capita (â); (iii) PWTP's CO2 emissions show a significant lag effect, of which the ratio of secondary industry accounts for the most significant impact. According to the research results, we put forward relevant targeted measures to achieve China's carbon emissions peak commitments in 2030: (1) PWTP should give priority to encouraging the development of technology and strengthening the utilization of new energy and renewable energy; (2) PWP should give priority to reducing energy intensity, optimizing the industrial structure and accelerating the process of urbanization; (3) CO2 emission reduction in PWTP is a long-term task, it is necessary to adhere to the optimization and adjustment of the industrial structure
Clean Electricity from the Detroit River: A Novel Hydro-Generator
ME450 Capstone Design and Manufacturing Experience: Winter 2008The VIVACE (Vortex Induced Vibration Aquatic Clean Energy) hydroelectric converter is a device that can be implemented anywhere that there is fluid flow. It works by converting the energy produced by Vortex Induced Vibrations (VIV) into linear oscillation motion. This motion is then converted into electrical energy through a Power Take Off (PTO) system. Our goal was to come up with a design that is robust, cost-effective, scalable, efficient, and environmentally friendly. Our design is a linear induction generator that works by passing a magnet over a non-corrosive tube containing coiled wire. This produces an electrical current through electromagnetic induction which will then be used to produce power.Prof. Michael Bernitsashttp://deepblue.lib.umich.edu/bitstream/2027.42/58692/1/me450w08project10_report.pd
Antitumor Research on Artemisinin and Its Bioactive Derivatives
Abstract Cancer is the leading cause of human death which seriously threatens human life. The antimalarial drug artemisinin and its derivatives have been discovered with considerable anticancer properties. Simultaneously, a variety of target-selective artemisinin-related compounds with high efficiency have been discovered. Many researches indicated that artemisinin-related compounds have cytotoxic effects against a variety of cancer cells through pleiotropic effects, including inhibiting the proliferation of tumor cells, promoting apoptosis, inducing cell cycle arrest, disrupting cancer invasion and metastasis, preventing angiogenesis, mediating the tumor-related signaling pathways, and regulating tumor microenvironment. More importantly, artemisinins demonstrated minor side effects to normal cells and manifested the ability to overcome multidrug-resistance which is widely observed in cancer patients. Therefore, we concentrated on the new advances and development of artemisinin and its derivatives as potential antitumor agents in recent 5Â years. It is our hope that this review could be helpful for further exploration of novel artemisinin-related antitumor agents. Graphical Abstrac
Self-reported sleep status and influencing factors: a web-based national cross-sectional survey in China
AbstractObjectives To investigate self-reported sleep duration, sleep timing, sleep status and influencing factors in the Chinese population.Methods This web-based cross-sectional survey was conducted in 2022, covering 31 provinces (91%) in China. 11,000 questionnaires were collected, of which 8970 were valid for analysis. Self-reported sleep habits, problems and quality were investigated. Good or fair sleep ratings, enough duration, regular, with no sleep disturbances and <30âmin sleep latency was defined as a composite variable: âGood sleepâ. Factors influencing sleep patterns and âGood sleepâ were analyzed by multivariate logistic regression.Results Most participants sleep less than 7âh per night (55.13%), usually go to bed at 10â12âpm (47.99%), wake up at 6â8 am (49.86%), and take less than 30âmin to fall asleep (66.30%) with regular sleep schedule (76.01%). Only 12.36% have âGood sleepâ. In the past 3âmonths, 46.80% of the participants reported symptoms of insomnia, and 21.54% had snoring problems. Among the adults, the young, males, college students, freelancers, and those who resided in urban areas and pandemic-free areas slept later, and the northerners woke up earlier. The adults with low-moderate and moderate income and the minors at elementary and middle school slept earlier and woke up earlier. Mid-aged adults who often napped at noon were more likely to have âGood sleepâ than any other age group, and urban dwellers with the same habit were more likely to have âGood sleepâ than people dwelled in other regions. While people who slept late, woke up too early or too late, slept too little or too much, resided at GMT 7â8 area or pandemic area, had high income, or took up some occupations (entrepreneurs/individuals, professionals, manual and non-manual workers, housewives) were less likely to get a âGood sleepâ.Conclusions The national survey provided a sleep profile of the Chinese population. Both socio-economic status and personal sleep hygiene habits had an impact on âGood sleepâ
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