We propose a distributed randomized policy iteration algorithm for infinite horizon dynamic programming problems for which the control at each stage is m-dimensional. The traditional policy iteration ...algorithm involves performing a minimization over an m-dimensional constraint set and has a computational complexity that increases exponentially in m, resulting in an intractable combinatorial search problem. In each iteration, our algorithm performs a series of sequential minimizations followed by policy evaluation and policy improvement using the policy that attains the minimum cost over the sequential minimizations. Our algorithm is well-suited for parallel computation, has a complexity that increases linearly in m, and converges to an agent-by-agent optimal policy. We characterize sufficient conditions for which our algorithm generates a globally optimal policy that coincides with that obtained from standard policy iteration.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
Fresh harvested walnuts are dehulled, washed, and then dried by hot air (HA) as a continuous process in the industry. The objective of the current work was to study the walnut structure and ...investigate its effect on the moisture transfer characteristics during the walnut soaking and drying processes. Moisture transport pathways into the walnuts were determined using fluorescence tracer approach, and the hydration kinetics of walnuts under different soaking temperatures (15, 25, and 35 °C) was studied using Peleg model. HA drying experiments in single layer in a self-designed automatic HA dryer at 43 °C and air velocity of 1.41 m/s. The influence of the stem pore (sealed and non-sealed) and the soaking process (0, 2- and 5-min soaking time) on the walnut drying characteristics were investigated systematically. The results indicated that both the presence of the stem pore and the soaking time had significant influence (p < 0.05) on the hydration and drying characteristics of walnuts. Moisture absorptions through the stem pore and the shell were equally important during the soaking process. Two to five minutes soaking process led to 2-4 h additional drying time. This study contributed valuable knowledge for the simulation and prediction of moisture transfer characteristics during the walnut soaking and drying processes. The findings from this study could potentially be applied to the walnut drying industry for more efficient processing
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BFBNIB, DOBA, GIS, IJS, IZUM, KILJ, KISLJ, NUK, PILJ, PNG, SAZU, UILJ, UKNU, UL, UM, UPUK
Iron sequestration by host proteins contributes to the defence against bacterial pathogens, which need iron for their metabolism and virulence. A Pseudomonas aeruginosa mutant lacking all three known ...iron acquisition systems retains the ability to grow in media containing iron chelators, suggesting the presence of additional pathways involved in iron uptake. Here we screen P. aeruginosa mutants defective in growth in iron-depleted media and find that gene PA2374, proximal to the type VI secretion system H3 (H3-T6SS), functions synergistically with known iron acquisition systems. PA2374 (which we have renamed TseF) appears to be secreted by H3-T6SS and is incorporated into outer membrane vesicles (OMVs) by directly interacting with the iron-binding Pseudomonas quinolone signal (PQS), a cell-cell signalling compound. TseF facilitates the delivery of OMV-associated iron to bacterial cells by engaging the Fe(III)-pyochelin receptor FptA and the porin OprF. Our results reveal links between type VI secretion, cell-cell signalling and classic siderophore receptors for iron acquisition in P. aeruginosa.
Moral disengagement is an essential concept in organizational behavioral ethics, as it is strongly related to employee behaviors and attitudes. What is not clear, however, is which leader traits are ...directly associated with employees' moral disengagement and which are indirectly associated with unethical behavior. This study draws on a social cognitive perspective that links leaders' other-oriented perfectionism (LOOP) with unethical employee behavior. Specifically, we propose that LOOP provides employees with excuses and encouragement to engage in unethical pro-organizational behavior (UPB).
We analyzed data collected from 266 full-time employees at two-time points, and used mediated and moderated structural equation models to test the hypotheses, and the findings largely support our claims.
The results suggest that LOOP effectively promotes employees' involvement in UPB. Moderated mediation tests suggest that the positive indirect impact of LOOP on employees' unethical behavior via moral disengagement was attenuated by higher employees' moral identity.
In summary, the results indicate that when leaders emphasize only perfection and make unrealistic demands on their employees, the latter perceive that engaging in unethical behavior is demanded by the leader, that the responsibility is not theirs, and thus they are more willing to engage in unethical behavior. This study discusses the implications of these findings from both practical and theoretical perspectives.
A hierarchical energy optimization management model is established and a multi-microgrid operation strategy that mixes the battery and the power interaction designed to strengthen the system output ...capability. This study carries out dynamic optimization to achieve optimal economic benefits of active distribution network with multi-microgrid system. An improved sparrow search algorithm is developed to achieve an optimal energy configuration by integrating Bernoulli chaotic mapping, Lévy flight, mutation, crossover and competition. The superiority of the improved sparrow search algorithm is demonstrated by the results of different test functions and evaluation indicators. The effectiveness of the proposed method is verified by solving and analyzing the optimal configuration of energy management model. Case study results reveal that the active distribution network with multi-microgrid system has good economic and environmental benefits under various scenarios. The methods proposed are of great significance for the economic operation and environmental protection of multi-microgrid active distribution network.
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BFBNIB, GIS, IJS, IZUM, KILJ, KISLJ, NUK, PILJ, PNG, SAZU, UL, UM, UPUK
Coastal loess is a special loess deposit that is distributed around the Bohai Sea. The primary objective of this study was to investigate the physical index, mineralogical characteristics and ...collapse potential of coastal loess. The secondary objective was to survey the effect of fine silt particles (particle size 5–10 μm, 6.64–7.64φ) on the collapse process. We tested the specific gravity, moisture content, dry density, Atterberg limits, grain size distribution, mineralogy, and collapsibility characteristics in a laboratory; generated scanning electron microscopy (SEM) images; and performed Mercury intrusion porosometry (MIP) tests. The results of this investigation indicated that coastal loess has a moderately severe collapse potential. The collapsibility coefficient decreases with an increase in the initial water content; it initially increases and then decreases with an increase in vertical pressure. As revealed by the MIP test, the collapse produces a smaller porosity, and the middle pores are primarily responsible for the collapse. The relationship of the collapsibility coefficient and particles with a diameter < 10 μm reveals that fine silt particles (particle size 5–10 μm, 6.64–7.64φ) and clay particles (particle size < 5 μm, >7.64φ) have the same tendency in terms of their effect on collapse. These results and analyses are important to improve the engineering construction safety in coastal zone loess areas and achieve a better understanding of loess properties compared with loess from a typical loess-paleosol section.
•Surveyed the particle and pore size distribution, Atterberg limits and mineralogical characteristics of Coastal loess.•Obtained the collapsibility of Coastal loess, and proposed the relationship between collapsibility coefficient and micro indexes based on the results of SEM and MIP tests.•Discussed the effect of fine silt particles (5-10 μm) on the collapse process.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
Copiotrophic bacteria that respond rapidly to nutrient availability, particularly high concentrations of carbon sources, play indispensable roles in marine carbon cycling. However, the molecular and ...metabolic mechanisms governing their response to carbon concentration gradients are not well understood. Here, we focused on a new member of the family Roseobacteraceae isolated from coastal marine biofilms and explored the growth strategy at different carbon concentrations. When cultured in a carbon-rich medium, the bacterium grew to significantly higher cell densities than
DSS-3, although there was no difference when cultured in media with reduced carbon. Genomic analysis showed that the bacterium utilized various pathways involved in biofilm formation, amino acid metabolism, and energy production via the oxidation of inorganic sulfur compounds. Transcriptomic analysis indicated that 28.4% of genes were regulated by carbon concentration, with increased carbon concentration inducing the expression of key enzymes in the EMP, ED, PP, and TCA cycles, genes responsible for the transformation of amino acids into TCA intermediates, as well as the
genes for thiosulfate oxidation. Metabolomics showed that amino acid metabolism was enhanced and preferred in the presence of a high carbon concentration. Mutation of the
genes decreased cell proton motive force when grown with amino acids and thiosulfate. In conclusion, we propose that copiotrophy in this Roseobacteraceae bacterium can be supported by amino acid metabolism and thiosulfate oxidation.
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IZUM, KILJ, NUK, PILJ, PNG, SAZU, UL, UM, UPUK
Background During the critical formative years of college, active participation in sports not only helps to alleviate stress, but also promotes the development of healthy habits. Although the ...multifaceted benefits of exercise have been widely recognized, there is a relative dearth of research on the relationship between personality traits, particularly college students’ self-oriented perfectionism (SOP), and exercise participation. Methods A questionnaire survey of 374 college students was conducted using the snowball sampling method. SPSS 26.0 and Mplus 8.3 were employed in this study to analyze the correlations between the variables, and on this basis, the effect of SOP on exercise participation was examined. The study also used 5,000 bootstrap samples and a 95% bias-corrected confidence interval to test the significance of the mediating effects. Results Correlation analysis showed that SOP was positively correlated with exercise participation. Harmonious passion and obsessive passion were positively correlated with SOP, and exercise participation. Further, the results of structural equation analysis revealed that SOP increased exercise participation. Harmonious passion and obsessive passion positively mediated the effect between SOP and exercise participation, respectively. Conclusion This study provides new perspectives to better understand college students’ exercise participation, emphasizing the importance of SOP and its influence on exercise participation through harmonious and obsessive passions. These findings have important implications for the development of effective exercise promotion strategies.
Background
With the popularity of social media platforms, the use of social networks challenges the well-being and mental health of athletes.
Motivation
Despite ongoing scholarly discussions about ...the effects of passive use of social network sites, few studies have examined the relationship between the passive use of social network sites and mental health in young athletes from a social comparison perspective.
Hypothesis
To address this research gap, we draw on the social comparison and developmental systems theories to explore the mediating effect of upward social comparison on passive social network site use and mental health, as well as the moderating effects of positive psychological capital.
Methods
We analyzed data about 350 young athletes from professional Chinese sports universities.
Results
As predicted, passive use of social network sites by young athletes increased anxiety (β = 0.26,
p
< 0.001) and decreased subjective well-being (β = −0.35,
p
< 0.001). Upward social comparisons had positive (β = 0.22,
p
< 0.001) and negative (β = −0.34,
p
< 0.001) mediating effects in passive social network site use and anxiety/subjective well-being. Positive psychological capital played a moderating effect between upward social comparison and anxiety (β = −0.28,
p
< 0.001), and subjective well-being (β = 0.24,
p
< 0.001); the moderated mediation effect was also supported.
Conclusion
Our study informs the current research by highlighting the importance of upward social comparison as a critical mechanism and positive psychological capital as a boundary condition. We suggest actively maintaining and enhancing positive psychological capital to mitigate the adverse effects of upward social comparison.
Abstract
Background
The relationship between the medical characteristics of lung cancers and computer tomography (CT) images are explored so as to improve the early diagnosis rate of lung cancers.
...Methods
This research collected CT images of patients with solitary pulmonary nodule lung cancer, and used gradual clustering methodology to classify them. Preliminary classifications were made, followed by continuous modification and iteration to determine the optimal condensation point, until iteration stability was achieved. Reasonable classification results were obtained.
Results
the clustering results fell into 3 categories. The first type of patients was mostly female, with ages between 50 and 65 years. CT images of solitary pulmonary nodule lung cancer for this group contain complete lobulation and burr, with pleural indentation; The second type of patients was mostly male with ages between 50 and 80 years. CT images of solitary pulmonary nodule lung cancer for this group contain complete lobulation and burr, but with no pleural indentation; The third type of patients was also mostly male with ages between 50 and 80 years. CT images for this group showed no abnormalities.
Conclusions
the application of gradual clustering methodology can scientifically classify CT image features of patients with lung cancer in the initial lesion stage. These findings provide the basis for early detection and treatment of malignant lesions in patients with lung cancer.
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