Previous work showed that animals have demonstratedremarkable adaptability by actively integrating into urban environments. However, there is no essential difference between urban andrural areas but food availabilit...
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Previous work showed that animals have demonstratedremarkable adaptability by actively integrating into urban environments. However, there is no essential difference between urban andrural areas but food availability. The behavioral mechanisms and processes by which animals adapt to cities still require further experimental validation. In this study, field surveys of the flight initiation distance (FId) of black-headed gulls (Chroicocephalus ridibundus) were performed at three scenic sites in Kunming City, Yunnan, southwest china. Ourresults showed that, within the same area, the FId of black-headed gulls was significantly shorter in areas with increased human activity. Moreover, in areas with earlier human contact, black-headed gulls showed shorter FId. The FIddata were further analyzed by a multilayer perceptron regression model with a neural network (ANN-MLP) approach to delineate FId thresholds for black-headed gulls in different human disturbance spots. The analysis revealed that black-headed gulls exhibit a high degree of behavioral flexibility in cities, with food availability playing a keyrole in increasing the birds' tolerance to humans. These findings highlight the significant impact of human behaviors, such as feeding, on wildlife behavior patterns. Understanding this mechanism is essential for understanding the coexistence of humans and wildlife. The establishment of FId models for black-headed gulls will provide new possibilities and tools for animal behaviorresearch.
The objective of this study was to analyse the difference in sensory flavour and volatile compounds among the three processing methods of soy whey, as well as to establish an evaluation model representing the correlat...
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The objective of this study was to analyse the difference in sensory flavour and volatile compounds among the three processing methods of soy whey, as well as to establish an evaluation model representing the correlation between sensory flavour and volatile compounds. The results showed that the soy whey produced by the boiling-to-filtering method (BFM) exhibited a higher total soluble solid (TSS) content and total flavonoid content (TFC) compared to that of the repeated boiling-to-filtering method (rBFM) and the filtering-to-boiling method (FBM), while rBFM soy whey showed a higher total protein content (TPC). The sensory analysis showed that the FBM soy whey exhibited an intense beany flavour and grease odour. The SPME/GC-MS results showed that FBM soy whey exhibited more categories and higher contents of flavour compounds, particularly for alcohols and aldehydes. 1-Octen-3-ol, n-hexanol, hexanal and nonanal were the main volatile compounds influencing soy whey with different processing methods. The evaluation model revealed that the beany flavour was close to FBM soy whey and highly correlated with 1-octen-3-ol, n-hexanol, hexanal, heptanal and 2-ethyl furan. (E, E)-2,4-Heptadienal, (E, E)-2,4-nonadienal and octanal were close to FBM and highly correlated with grease and bean fragrance. decanal, ethyl caproate and ethyl caprylate were highly correlated with the floral aroma and close to FBM soy whey. Sweet and fruity aromas were associated with rBFM soy whey and highly correlated with 3-methyl butanal, (E)-2-nonenal and nonanal. The milk aroma was close to BFM soy whey and highly correlated with 2-ethylfuran, decanal, ethyl caprylate and ethyl caproate. Overall, rBFM and BFM soy whey contained higher levels of protein and flavonoids and exhibited less beany flavour, potentially offering greater nutritional value. In contrast, the FBM soy whey exhibited a higher content of volatile flavour compounds, especially 1-octen-3-ol, n-hexanol, hexanal and 2-ethyl furan.
Meshing temperature analyses of polymer gears reported in the literature mainly concern the effects of various material combinations and loading conditions, as their impacts could be seen in the first few meshing cycl...
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Meshing temperature analyses of polymer gears reported in the literature mainly concern the effects of various material combinations and loading conditions, as their impacts could be seen in the first few meshing cycles. However, the effects of tooth geometry parameters could manifest as the meshing cycles increase. This study investigated the effects of tooth geometry parameters on the multi-cycle meshing temperature of polyoxymethylene (POM) worm gears, aiming to control the meshing temperature elevation by tuning the tooth geometry. Firstly, a finite element (FE) model capable of separately calculating the heat generation and simulating the heat propagation was established. Moreover, an adaptive iteration algorithm was proposed within the FE framework to capture the influence of the heat generation variation from cycle to cycle. This algorithm proved to be feasible and highly efficient compared with experimental results from the literature and simulatedresults via the full-iteration algorithm. Multi-cycle meshing temperature analyses were conducted on a series of POM worm gears with different tooth geometry parameters. The results reveal that, within the range of 14.5 degrees to 25 degrees, a pressure angle of 25 degrees is favorable forreducing the peak surface temperature and overall body temperature of POM worm gears, which influence flank wear and load-carrying capability, respectively. However, addendum modification should be weighed because it helps with load bearing but increases the risk of severe flank wear. This paper proposes an efficient iteration algorithm for multi-cycle meshing temperature analysis of polymer gears and proves the feasibility of controlling the meshing temperature elevation during multiple cycles by tuning tooth geometry.
The composited hydrogels derived from natural materials are getting attention in the field of cultured meat due to their advantages of biocompatibility anddegradability as cell scaffolds. In this work, two edible cro...
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The composited hydrogels derived from natural materials are getting attention in the field of cultured meat due to their advantages of biocompatibility anddegradability as cell scaffolds. In this work, two edible cross-linking agents, transglutaminase (TGase) and/or calcium ions, were successfully used to cross-link soy protein isolated (SPI) and soy dietary fiber (SdF) to fabricate different scaffolds. The prepared scaffolds were characterized by structural, hydration, rheological, and mechanical analysis. The double cross-linked scaffolds exhibited the highest compressive moduli compared to the single cross-linked scaffolds and had an excellent liquid absorbing ability of up to 309.45%, while its porosity was as high as 72.66%. In addition, NIH 3T3 cells were used to evaluate the biocompatibility of the scaffolds in vitro. The double cross-linked scaffolds could promote the expression of differentiation-related genes and were beneficial for cell adhesion and proliferation. In conclusion, the present research provides a new approach to prepare cell scaffolds using soybean resources, which could be used in cultured meat applications.
This article introduces the dissipative performance analysis into the formation control design for multiple unmanned surface vehicles (USVs) with exogenous disturbances. All USVs are coordinated under a leaderless fra...
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This article introduces the dissipative performance analysis into the formation control design for multiple unmanned surface vehicles (USVs) with exogenous disturbances. All USVs are coordinated under a leaderless framework, where the network communications are described by a set of undirected graphs varying in a Markovian switching manner. Without requiring continuously transmitted information, the memory sampled-data scheme is exploited to aperiodically sample the information of in-neighboring USVs for enabling discrete data transmission subject to time-varying delays dependent on Markovian jump modes. With the collection of the delayed sampling information, a nonfragile formation control protocol is novelly constructed not only to tolerate parameter perturbation but also to improve tuning performance. By defining formation error vectors facilitated with orthonormal transformation technique and algebraic graph theory, the concerned formation control problem is equivalently cast into analyzing the strict dissipativity of the resultant Markovian jump system with mode-dependent time-varying delays. To describe the holistic movement of the leaderless USV swarm, one promisingly derives a formation reference function characterized by a dynamical system with determined initial condition, whose state evolution is capable to be regulated. The validation of the theoretical results is performed by a water experiment.
Succinic acid (SA) is a promising platform chemical with broad applications in agricultural, food, and pharmaceutical industries. Microbial production of SA using Escherichia coli typically requires alkaline neutraliz...
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Succinic acid (SA) is a promising platform chemical with broad applications in agricultural, food, and pharmaceutical industries. Microbial production of SA using Escherichia coli typically requires alkaline neutralizers to maintain pH during fermentation, leading to elevated osmotic pressure that severely inhibits SA production. The strain ZZT215, evolved from AFP111 using two-step adaptive laboratory evolution (ALE) strategy, exhibited the improved Na+ tolerance and SA productivity without further genetic modification. In 5 L bioreactor fermentation, ZZT215 accumulated 87.02 g/L of SA with a productivity at 1.01 g/(Lddle dot>h), representing 24.9% and 21.7% increases compared to the parent strain AFP111, respectively. Transcriptomic analysis revealeddownregulated TCA cycle genes and upregulated ABC transporters, indicating metabolic adaptation to osmotic stress. These findings highlight the potential of multiple-step ALE for engineering robust microbial cell factories for SA and other high-value chemicals.
In order to reduce modeling workload and improve the accuracy of wooddensity measurement, a modeling method for establishing an overall model for multiple tree species was studied. Firstly, the wood cores anddrill r...
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In order to reduce modeling workload and improve the accuracy of wooddensity measurement, a modeling method for establishing an overall model for multiple tree species was studied. Firstly, the wood cores anddrill resistance of 9 tree species were collected. The absolute dry density, wood moisture content, and average drill resistance for each wood core were calculated. Secondly, the random forest algorithm was used to rank the relative importance of each factor affecting wooddensity, and factors with relative importance higher than 0.05 were selected as independent variables for building the overall mathematical model for total tree species and sub model for individual tree species. The results showed that: (1) the relative importance of tree species anddrill resistance on wooddensity was higher than 0.05;(2) the relative importance of moisture content anddrill usage frequency (less than 150 times) on wooddensity was lower than 0.05;(3) the average estimation accuracy of overall model was 91.42%, while that of the sub model was only 90.44%;(4) among the 9 tree species, the standarddeviation of the overall model for 5 tree species was lower than that of the sub model. The results showed that the accuracy and stability of the overall model were superior to those of the sub models, and it is feasible to establish an overall model to estimate wooddensity.
Ovarian tumor ubiquitinating 6A (OTUd6A) is a deubiquitinating enzyme whose aberrant expression has been linked to various diseases, including inflammation and prostate cancer. research indicates that deubiquitinating...
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Ovarian tumor ubiquitinating 6A (OTUd6A) is a deubiquitinating enzyme whose aberrant expression has been linked to various diseases, including inflammation and prostate cancer. research indicates that deubiquitinating enzymes (dUBs) play a significant role in spermatogenesis in mice. However, the role of OTUd6A in spermatogenesis remains unclear. To investigate the function of OTUd6A in mouse spermatogenesis, we generated Otud6a-knockout mice using the CrISPr/Cas9 system. Ourresults showed that OTUd6A is predominantly expressed in the testis and localized to the cytoplasm of spermatogonia and spermatocytes. Although no significant differences were observed in testicular size or morphology between Otud6a-knockout and wild-type mice, the knockout mice exhibited increased germ cell apoptosis, decreased epididymal sperm counts, abnormalities in sperm motility and subfertility. These findings indicate that Otud6a-knockout leads to male subfertility in mice.
Substantial effects of photochemical reaction losses of volatile organic compounds(VOCs)on factor profiles can be investigated by comparing the differences between daytime and nighttime dispersion-normalized VOC data ...
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Substantial effects of photochemical reaction losses of volatile organic compounds(VOCs)on factor profiles can be investigated by comparing the differences between daytime and nighttime dispersion-normalized VOC data resolved *** speciated VOC data measured in Shijiazhuang,china from May to September 2021 were used to conduct *** mean VOC concentration in the daytime and at nighttime were 32.8 and 36.0 ppbv,*** and aromatics concentrations in the daytime(12.9 and 3.08 ppbv)were lower than nighttime(15.5 and 3.63 ppbv),whereas that of alkenes showed the opposite *** concentration differences between daytime and nighttime for alkynes and halogenated hydrocarbonswere uniformly *** reactivities of the dominant species in factor profiles for gasoline emissions,natural gas anddiesel vehicles,and liquefied petroleum gas were relatively low and their profiles were less affected by photochemical *** losses produced a substantial impact on the profiles of solvent use,petrochemical industry emissions,combustion sources,and biogenic emissions where the dominant species in these factor profiles had high *** the profile of biogenic emissions was substantially affected by photochemical loss of isoprene,the low emissions at nighttime also had an important impact on its *** losses of highly active VOC species substantially reduced their concentrations in apportioned factor *** study results were consistent with the analytical results obtained through initial concentration estimation,suggesting that the initial concentration estimation could be the most effective currently availablemethod for the source analyses of active VOCs although with uncertainty.
Urban flooding poses a significant challenge in highly urbanized areas, necessitating effective solutions to enhance sustainable urban stormwater management. This study proposes an Integrated Green-Gray-Blue-Control (...
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Urban flooding poses a significant challenge in highly urbanized areas, necessitating effective solutions to enhance sustainable urban stormwater management. This study proposes an Integrated Green-Gray-Blue-Control (IGGBC) system as a comprehensive strategy for urban floodrisk mitigation. Through systematic scenario analysis, twelve distinct strategies were examined, including individual green, blue, and gray measures;combined green-blue, green-gray, blue-gray, and gray-green-blue (IGGB) approaches;and five integrated gray-green-blue-control (IGGBC3.2, IGGBC3.0, IGGBC2.8, IGGBC2.6, IGGBC2.4) systems. A 1d- 2d coupled hydrological-hydrodynamic model was employed to simulate urban flood inundation and evaluate the performance of various mitigation strategies. The results indicate that individual measures yielded limited improvements in mitigating urban flooding, as reflected in poor effectiveness index (EI) values. Among combined measures, the green-blue and green-gray combinations demonstrated negligible effectiveness, and the blue-gray combination slightly mitigated urban flooding but still showed insufficient EI values. Additionally, the IGGB measure provided moderate mitigation with a reasonable EI value. In contrast, the IGGBC3.2 measure significantly outperformed IGGB, increasing the inundation reduction ratio from 38.49% to 53.16% and enhancing the EI from 0.52 (good) to 1.00 (excellent), demonstrating its control measures' effectiveness in alleviating mutual constraints between stormwaterdrainage systems and flooddischarge channels. Notably, the IGGBC system also demonstrated excellent performance in mitigating flood inundation during high-return-periodrainfall events. However, a diminishing marginal effect was observed among the different integrated IGGBC systems (IGGBC3.2, IGGBC3.0, IGGBC2.8, IGGBC2.6, IGGBC2.4). This study provides valuable insights fordeveloping effective urban flood management strategies and makes a significant contribution to enhan
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