65 research outputs found
Unified Multi-Objective Genetic Algorithm for Energy Efficient Job Shop Scheduling
In recent years, people have paid more and more attention to traditional manufacturing’s environmental impact, especially in terms of energy consumption and related emissions of carbon dioxide. Except for adopting new equipment, production scheduling could play an important role in reducing the total energy consumption of a manufacturing plant. Machine tools waste a considerable amount of energy because of their underutilization. Consequently, energy saving can be achieved by switching machines to standby or off when they lay idle for a comparatively long period. Herein, we first introduce the objectives of minimizing non-processing energy consumption, total weighted tardiness and earliness, and makespan into a typical production scheduling model-the job shop scheduling problem, based on a machine status switching framework. The multi-objective genetic algorithm U-NSGA-III combined with MME (a heuristic algorithm combined with the MinMax (MM) and Nawaz–Enscore–Ham (NEH) algorithms) population initialization method is used to solve the problem. The multi-objective optimization algorithm can generate a Pareto set of solutions so that production managers can flexibly select a schedule from these non-dominated schedules based on their priorities. Three sets of numerical experiments have been carried out on the extended Taillard benchmark to verify this three-objective model’s effectiveness and the multi-objective optimization algorithm. The results show that U-NSGA-III has obtained better Pareto solutions in most test problem instances than NSGA-II and NSGA-III. Furthermore, the non-processing energy consumption is reduced by 46%-69%, which is 13-83% of the total energy consumption
Impact of pesticide regulations on mortality from suicide by pesticide in China: an interrupted time series analysis
BackgroundPesticide bans and regulatory restrictions have been shown to be effective strategies for preventing suicide in several countries. Suicide and suicide by pesticides have decreased significantly in China over the past two decades. However, whether the reduction was associated with pesticide regulation is unknown.MethodsThe monthly data on suicide and suicide by pesticide from 2006 to 2018 were obtained from China's Disease Surveillance Point (DSP) system. Information on China's pesticide regulations since 1970 was obtained from Pesticide Action Network International (PAN International), Joint Meeting on Pesticide Management Highly Hazardous Pesticides (JMPM HHP) lists, the website of the Ministry of Agriculture of China, Pesticide Information Network of China, and the Wan Fang database. Change point detection and policy analysis were combined to identify the time of any trend change breakpoint of suicide and suicide by pesticide. Interrupted time series analysis was used to investigate the pre- and post-breakpoint trends of monthly standardized rates in suicide and suicide by pesticide.ResultsThe standardized pesticide suicide rate decreased by 60.5% from 6.50 in 2006 to 2.56 per 100,000 in 2018. Larger declines were evident among people in urban areas (67.3%), female individuals (63.5%), and people aged 15–44 years (68.1%). The effect of policies banning highly hazardous organophosphorus pesticides (HHOP) [rate ratio (RR) = 0.993, 95% CIs (0.991–0.994)] in December 2008 and stopping domestic sales and use of paraquat aqueous solution (RR = 0.992, 95% CIs: 0.990–0.994) in July 2016 were more pronounced than regulating the paraquat-related products (RR = 1.003, 95% CIs: 1.002–1.004) in April 2012.ConclusionDeclines in suicide by pesticide in China occurred contemporaneously with regulatory bans and restrictions implemented on several pesticides, particularly in urban areas, among female individuals, and the relatively low age profile. These findings indicate the potential influence of these bans on trends of suicide by pesticides
Construction of Gene Expression Vector and Its Catalysis Efficiency in Bovine Fetal Fibroblast Cells
The FAT-1 protein is an n-3 fatty acid desaturase, which can recognize a range of 18- and 20-carbon n-6 substrates and transform n-6 polyunsaturated fatty acids (PUFAs) into n-3 PUFAs while n-3 PUFAs have beneficial effect on human health. Fat1 gene is the coding sequence from Caenorhabditis elegans which might play an important role on lipometabolism. To reveal the function of fat1 gene in bovine fetal fibroblast cells and gain the best cell nuclear donor for transgenic bovines, the codon of fat1 sequence was optimized based on the codon usage frequency preference of bovine muscle protein, and directionally cloned into the eukaryotic expression vector pEF-GFP. After identifying by restrictive enzyme digests with AatII/XbaI and sequencing, the fusion plasmid pEF-GFP-fat1 was identified successfully. The pEF-GFP-fat1 vector was transfected into bovine fetal fibroblast cells mediated by Lipofectamine2000TM. The positive bovine fetal fibroblast cells were selected by G418 and detected by RT-PCR. The results showed that a 1,234 bp transcription was amplified by reverse transcription PCR and the positive transgenic fat1 cell line was successfully established. Then the expression level of fat1 gene in positive cells was detected using quantitative PCR, and the catalysis efficiency was detected by gas chromatography. The results demonstrated that the catalysis efficiency of fat1 was significantly high, which can improve the total PUFAs rich in EPA, DHA and DPA. Construction and expression of pEF-GFP-fat1 vector should be helpful for further understanding the mechanism of regulation of fat1 in vitro. It could also be the first step in the production of fat1 transgenic cattle
The Assessment on Synergistic Activity of Ebselen and Silver Ion Against Yersinia pseudotuberculosis
Yersinia pseudotuberculosis is a foodborne zoonotic bacterium that is pathogenic to guinea pigs, rabbits, and mice. It also causes pseudotuberculosis in humans. However, it still lacked the scientific basis for control. Here, we found out that Ebselen (EbSe) exhibited synergistic antibacterial activity with silver nitrate (Ag+) against Y. pseudotuberculosis YpIII strain with high efficacy in vitro using UV-visible light absorption spectrum, 5,5’-dithiobis-(2-nitrobenzoic acid), laser scanning confocal microscope, flow cytometry, transmission electron microscopy and Western blotting assays. The depletion of total glutathione (GSH) amount and inhibition of thioredoxin reductase (TrxR) activity in thiol-dependent redox system revealed the destructiveness of EbSe-Ag+-caused intracellular oxidative stress. Furthermore, a YpIII-caused mice gastroenteritis model was constructed. EbSe-Ag+ significantly reduced bacterial loads with low toxicity. It also down-regulated the expression levels of interferon (IL)-1β and tumor necrosis factor-α, up-regulated the expression level of IL-10 on-site. All the in vivo results demonstrated the antibacterial activity and immune-modulatory property of EbSe-Ag+. Collectively, these results provided academic fundament for further analysis and development of EbSe-Ag+ as the antibacterial agents for pseudotuberculosis control
Roadmap on Perovskite Light-Emitting Diodes
In recent years, the field of metal-halide perovskite emitters has rapidly
emerged as a new community in solid-state lighting. Their exceptional
optoelectronic properties have contributed to the rapid rise in external
quantum efficiencies (EQEs) in perovskite light-emitting diodes (PeLEDs) from
<1% (in 2014) to approaching 30% (in 2023) across a wide range of wavelengths.
However, several challenges still hinder their commercialization, including the
relatively low EQEs of blue/white devices, limited EQEs in large-area devices,
poor device stability, as well as the toxicity of the easily accessible lead
components and the solvents used in the synthesis and processing of PeLEDs.
This roadmap addresses the current and future challenges in PeLEDs across
fundamental and applied research areas, by sharing the community's
perspectives. This work will provide the field with practical guidelines to
advance PeLED development and facilitate more rapid commercialization.Comment: 103 pages, 29 figures. This is the version of the article before peer
review or editing, as submitted by an author to Journal of Physics:
Photonics. IOP Publishing Ltd is not responsible for any errors or omissions
in this version of the manuscript or any version derived from i
The "Rights Awakening" of Chinese Migrant Workers: Beyond the Generational Perspective
In the spring of 2010, the strike of the Honda workers in Nanhai instigated an on-going discourse on the rights awakening of the new generation of migrant workers. Since then, much has been written about these young workers, generally described as more pro-active and ready to stand up against their employers than the older and more subservient generation. Drawing from statistical findings from two factory-gate surveys in the metal mechanics and garment sectors in Shenzhen, this paper tests two hypotheses: (a) that workers of the younger generation are more cognizant of their legal rights than older workers; (b) that the younger generation wants to work fewer hours and to enjoy life more. We argue that this popular image of the younger generation of migrant workers is one-dimensional and reductive, as it focuses only on generational differences as an explanatory factor for worker activism, while ignoring other issues such as types of industries and payment systems. In this paper, we purport that these elements play important roles in shaping the attitude of this younger generation toward their work and rights
Effect of Land Use Change on Ecosystem Service Value in Dujiangyan City
In order to evaluate the impact of land use change on ecosystem service value in Dujiangyan City, through equivalent factor method, qualitative and quantitative analysis is carried out on the dynamic change of land use change and its caused ecosystem service value in Dujiangyan City from 2010 to 2016. The results show that: (1) Dujiangyan city land use changes a large extent, with the extension of construction land expansion as the main increase part, and at the cost of the reduction of arable land and grassland area. (2) Over the past 7 years, the total value of ecosystem services in Dujiangyan city followed a law of first rising and then falling, showing an overall rising trend, with a total increase of 19.2244 million yuan. (3) The accuracy of the ecological value coefficient of woodland and grassland will greatly affect the value assessment of ecosystem services in Dujiangyan city. (4) From the relationship between land use type and ecosystem service value, cultivated land and construction land are negatively correlated with ecosystem service value, on the contrary, forest land, grassland, water area and construction land are positively correlated with ecosystem service value. In general, the land use of Dujiangyan City did not cause obvious damage to the ecological environment, but also cannot ignore the impact of land use changes on the environment in the process of economic development. It is necessary to control the growth of construction land area, promote the conservation and rational development of Eco-tourism area in Dujiangyan City, maintain the stability of ecosystem services in Dujiangyan City, and realize the strategy of sustainable development of Social-Economic-Ecological benefits
Longitudinal association between the dynamic nature of depression with lower urinary tract symptoms suggestive of benign prostatic hyperplasia (LUTS/BPH)
Abstract Background Depression is associated with an increased risk of lower urinary tract symptoms suggestive of benign prostatic hyperplasia (LUTS/BPH). Whether the dynamic nature of depression affects the incidence of LUTS/BPH remains unknown. A four-year cohort study based on the China Health and Retirement Longitudinal Study (CHARLS) was conducted to assess their association. Methods This study included 3433 Chinese men from the CHARLS 2011, representative of > 95 million individuals. All eligible individuals underwent three assessments of LUTS/BPH and depression in 2011, 2013 and 2015. The dynamic nature of depression was classified as acute depression with remission, acute depression with recurrence, or chronic major depression. Weighted, generalized additive analyses with three binomial models were used to investigate the relationship between LUTS/BPH and the dynamic nature of depression. Results During the four-year follow-up, 11.5% (95% confidence interval [95% CI] = 9.5-13.3%) of Chinese men were diagnosed with newly incident LUTS/BPH. Meanwhile, there were 60.6% (95% CI = 58.5-62.7%) of the individuals without depression and 8.9% (95% CI = 7.9-10%) of the individuals with chronic major depression. A total of 25.1% (95% CI = 23.4-26.9%) and 5.4% (95% CI = 4.6-6.3%) of the individuals were categorized as acute depression with remission and recurrence. After weighted, adjusted all included confounding risk factors, chronic major depression (RR = 1.63, 95% CI = 1.14–2.33, P < 0.01) but not acute depression with remission (RR = 1.2, 95% CI = 0.92–1.56, P = 0.18) and recurrence (RR = 1.32, 95% CI = 0.82–2.10, P = 0.26) significantly increased the incidence of LUTS/BPH compared with no depression. The subgroup analysis showed that the above relationships appeared to be evident among Chinese men < 60 years. Conclusions Our results suggest that the dynamic nature of depression has a different effect on the incidence of LUTS/BPH. The monitoring and treatment of depression are important in preventing LUTS/BPH
Does City Public Service Distance Increase Sense of Gain to Public Health Service? Evidence from 1394 Migrant Workers in Six Provinces
Increasing the well-being of migrant workers is one of the key objectives of promoting equality and safe, people-oriented, and sustainable social development, as well as inclusive globalization. With the equalization reform of the public health system and the reduction of frictions between cities, the well-being of the sense of gain to public health service (SGPHS) of migrant workers has attracted widespread attention. Based on the migrant worker thematic survey data in 2017 and the city statistical data in six destination cities, this study constructed and measured the sense of gain to public health service index and city public service distance index, and then studied the effects of city public service distance on the SGPHS of migrant workers and the heterogeneous effect. The results showed that the SGPHS of Chinese migrant workers is at a moderate level and presents spatial differences. Under the dual mechanism of preference reinforcement effect and public service discount effect, the effect of city public service distance on the SGPHS of migrant works shows an inverted U-shaped relationship, and the results of the endogeneity test by the generalized propensity score matching model are robust. The city public service distance has a significant non-linear effect on the public health service accessibility and provision for migrant workers, as well as on second-generation, low-income migrant workers, and migrant workers in central and western regions. The results provide beneficial insights for the formulation of rational public service policies
Integrated Emergy and Economic Evaluation of Huzhou Mulberry-Dyke and Fish-Pond Systems
The Huzhou mulberry-dyke and fish-pond system (HMFS) is a compound structure of agriculture with interaction among several subsystems, and it is an effective example of a circular economy by exogenous input and waste reduction to maintain a harmonious relationship between humans and nature. As increases in rural urbanization and transition of peasants occur, the traditional systems remain in a constant state of change, along with different kinds of adaptation models. In this study, two main existing models are examined by field investigation and extensive literature analysis. Emergy theory and methods are adopted to make a further quantitative analysis from emergy structure and indices synthetically and systemically. In this process, the models of HMFS are split into several subsystems, including mulberry dyke, fish pond, rape dyke, and silkworm, in terms of a modularization approach. The proportion of combinations among different subsystems is calculated by the average production level of local peasants. The empirical results of emergy analysis indicate that the two existent patterns of HMFS are themselves superior in terms of environmental capacity and commercial efficiency. The mulberry⁻silkworm⁻fish model possesses more sustainable characteristics than the rape⁻fish model by the mass flow and energy flux. In addition, the rape⁻fish model may obtain considerably better economic returns by more inorganic resources, and thus achieve higher economic benefits. Therefore, the rape⁻fish model may be an evolutionary model to make directions for further research and protection, while other adaptive units are introduced to form multiple systems
- …