The Northeast China cold vortex (NCCV) during late summer (from July to August) is identified and classified into three types in terms of its movement path using machine learning. The relationships ...of the three types of NCCV intensity with atmospheric circulations in late summer, the sea surface temperature (SST), and Arctic sea ice concentration (SIC) in the preceding months, are analyzed. The sensitivity tests by the Community Atmosphere Model version 5.3 (CAM5.3) are used to verify the statistical results. The results show that the coordination pattern of East Asia-Pacific (EAP) and Lake Baikal high pressure forced by SST anomalies in the North Indian Ocean dipole mode (NIOD) during the preceding April and SIC anomalies in the Nansen Basin during the preceding June results in an intensity anomaly for the first type of NCCV. While the pattern of high pressure over the Urals and Okhotsk Sea and low pressure over Lake Baikal during late summer—which is forced by SST anomalies in the South Indian Ocean dipole mode (SIOD) in the preceding June and SIC anomalies in the Barents Sea in the preceding April—causes the intensity anomaly of the second type. The third type is atypical and is not analyzed in detail. Sensitivity tests, jointly forced by the SST and SIC in the preceding period, can well reproduce the observations. In contrast, the results forced separately by the SST and SIC are poor, indicating that the NCCV during late summer is likely influenced by the coordinated effects of both SST and SIC in the preceding months.
Extracellular enzymes (EEs) play vital roles in the transformations of soil organic matter, yet the regulators of EE activity remain unclear. Inducible EE production predicts that EE activity is ...determined by microbial nutrient status. Alternatively, EE production can be constitutive (continuous and baseline-level expression of EE gene regardless of the nutrient status), and in this case EE gene abundance potentially affects EE activity. Here, we examined whether EE gene abundance was a key regulator of EE activity along a vegetation restoration chronosequence. For the four hydrolytic EEs related to microbial acquisition of carbon, nitrogen and phosphorus, their gene abundance ratios (obtained from metagenomic sequencing) were positively related to corresponding activity ratios (R2 = 0.43–0.94). These relationships were maintained in the structural equation modeling when the effects of microbial nutrient status and soil property were considered. The gene-enzyme link was further confirmed by the positive relationship between the absolute abundance of phoD gene (obtained from qPCR analysis) and the alkaline phosphomonoesterase activity. Overall, our results suggest that constitutive EE production may contribute significantly to soil EE activity. The direct gene-enzyme link highlights the development of gene-informed Earth system models to better predict the soil carbon dynamics under global change.
•The “gene-enzyme” relationship was examined along a vegetation restoration chronosequence.•Extracellular enzyme (EE) activity was tightly linked to its gene abundance.•Constitutive EE production may contribute significantly to soil EE activity.
•WMA mixtures containing high percentage of RAP were produced using different WMA additives.•WMA additives lowered the mixing and compaction temperatures of mixtures.•Performance evaluation on ...rutting, low temperature cracking, moisture damage, aging, and fatigue of mixtures.•Effect of WMA additives and RAP on the performance of mixtures was pronounced.
This study aims to evaluate the laboratory performance of warm mix asphalt containing reclaimed asphalt pavement (WMA–RAP) materials. The WMA mixtures containing 0% and 40% RAP were produced using Evotherm-DAT and S-I WMA additives. The laboratory performance tests included rutting, bending, freeze–thaw splitting, Marshall immersion, aging, freeze–thaw cycles splitting, and fatigue tests. The moisture and low temperature cracking resistance were evaluated for aged mixtures. The results showed the WMA mixtures without RAP performed better moisture and low temperature cracking resistance, and lower rutting resistance than the WMA–RAP mixtures. The WMA mixtures suffered from the short-term aging exhibited a slight increase as compared to the unaged mixtures, whereas the long-term aging resulted in a distinct reduction in terms of the moisture resistance. After the short- and long-term aging, the WMA mixtures exhibited a greater decrease than the unaged mixtures in terms of the low temperature cracking resistance. The tensile strength ratio (TSR) results of the WMA–RAP mixtures generally decreased with the increase of freeze–thaw cycles, while the TSR results showed an obvious increase after three freeze–thaw cycles. The addition of RAP significantly reduced the fatigue resistance of the WMA–RAP mixtures in comparison with the WMA mixtures without RAP. Based upon the study findings, the moisture resistance under freeze–thaw cycles conditioning remains an issue to be considered in the WMA–RAP mixtures.
AbstractA new approach for the characterization of linear viscoelastic (LVE) behavior of asphalt concrete is presented in this study. The proposed approach uses the associated function of the ...original Havriliak-Negami (HN) formulation to model the complex modulus of the material. The model coefficients are determined in two steps. First, the coefficients associated with the complex plane representation of complex modulus are solved in the Cole-Cole domain. Second, the coefficients related to the time-temperature shifting are determined. The results show that the approach can accurately characterize the LVE properties of asphalt concrete contained in the entire data set for the complex modulus. The approach overcomes several shortcomings in the conventional method of constructing a viscoelastic function master curve by fitting a sigmoidal function to test results. Each model coefficient in the proposed approach has a clear physical meaning in interpreting the LVE behavior of asphalt concrete; the same values of model coefficients can be used to construct the master curves of storage modulus, loss modulus, dynamic modulus, and phase angle. Also, the Kronig-Kramers relations are automatically satisfied because the mathematical forms of various viscoelastic functions are theoretically derived from the same complex modulus model, and thus, the results are in compliance with LVE theory. The proposed approach provides a unified and consistent way to characterize the LVE properties of asphalt concrete.
The cell orientation characteristics of the natural combs of honey bees have received much research attention. Although natural combs have been shown to be composed of cells with three ...orientations-vertical, intermediate (oblique), and horizontal-the proportion of comb cells in these three orientations varies. Knowledge of the comb-building preferences of honey bees is essential for the installation of wax comb foundations, and clarification of the cell orientation characteristics of natural honey bee combs is important for beekeeping. The purpose of this study was to determine the cell orientation characteristics of natural combs of Eastern honey bees (Apis cerana cerana) and Western honey bees (Apis mellifera ligustica). Newly built combs were used to measure the orientation of hexagonal cells and calculate the proportion of cells in different orientations relative to the total number of cells. The number of eggs laid by queens in the cells of different orientations was also determined. The orientation of cells in the natural combs of Eastern and Western honey bees was determined based on the value of the minimum included angle between the pair of parallel cell walls and a vertical line connecting the top and bottom bars of the movable frame in the geometric plane of the comb: 0°≤θ≤10°, 10°<θ≤20°, and 20°<θ≤30° for vertical, intermediate, and horizontal orientations, respectively. Natural combs were composed of cells with at least one orientation (vertical or horizontal), two orientations (vertical + intermediate (oblique) or vertical + horizontal), or three orientations (vertical + intermediate + horizontal), and the proportions of combs with the three aforementioned configurations differed. Both Eastern honey bees and Western honey bees preferred building combs with cells in a vertical orientation. Queens showed no clear preference for laying eggs in cells of specific orientations. The results of this study provide new insight that could aid the production and cutting of wax comb foundations of Eastern and Western honey bees. Our study highlights the importance of installing wax comb foundations compatible with the comb-building preferences of bees.
Abstract
Gravitational waves from the neutron star coalescence GW170817 were observed from the inspiral, but not the high frequency postmerger nuclear matter motion. Optomechanical white light signal ...recycling has been proposed for achieving broadband sensitivity in gravitational wave detectors, but has been reliant on development of suitable ultra-low loss mechanical components. Here we show demonstrated optomechanical resonators that meet loss requirements for a white light signal recycling interferometer with strain sensitivity below 10
−24
Hz
−1/2
at a few kHz. Experimental data for two resonators are combined with analytic models of interferometers similar to LIGO to demonstrate enhancement across a broader band of frequencies versus dual-recycled Fabry-Perot Michelson detectors. Candidate resonators are a silicon nitride membrane acoustically isolated by a phononic crystal, and a single-crystal quartz acoustic cavity. Optical power requirements favour the membrane resonator, while thermal noise performance favours the quartz resonator. Both could be implemented as add-on components to existing detectors.
•Relationship between MPD and SMTD has been analyzed.•Spatiotemporal evolution of texture depth on RIOH track has been presented.•Hurst exponent is used to describe texture evolution characteristics.
...The spatial and temporal variability of road surface texture with the environment is closely related to the management and maintenance of pavement performance. To understand the spatiotemporal evolution, accelerated loading test was carried out during a four-year period on Research Institute of Highway (RIOH) track. Statistical and rescaled range (R/S) analysis were introduced to analyze the texture depth data collected using an automatic detection vehicle. As a result, even though a high linear correlation, there are significant differences statistically between the two indexes mean profile depth (MPD) and sensor measured texture depth (SMTD). Further, the spatial variability of texture depth, generally between 5% ∼ 15%, does not change obviously with service environments. However, the variation range of texture depth with time is as low as 0.2 mm and as high as 0.75 mm. The climate-loading effect increases the variation range of MPD more than the climate effect. Through R/S analysis, the Hurst exponent of the MPD sequence is<0.5, indicating the evolution of texture depth is an anti-persistent alternating process between increase and decrease. In addition, the average cycle period, representing the past duration of events affecting future trend, is generally<8 months. These studies took some new insights into the evolution behaviors of texture depth, providing the groundwork for estimating and setting texture level.
When designing infographics, general users usually struggle with getting desired color palettes using existing infographic authoring tools, which sometimes sacrifice customizability, require design ...expertise, or neglect the influence of elements' spatial arrangement. We propose a data-driven method that provides flexibility by considering users' preferences, lowers the expertise barrier via automation, and tailors suggested palettes to the spatial layout of elements. We build a recommendation engine by utilizing deep learning techniques to characterize good color design practices from data, and further develop InfoColorizer, a tool that allows users to obtain color palettes for their infographics in an interactive and dynamic manner. To validate our method, we conducted a comprehensive four-part evaluation, including case studies, a controlled user study, a survey study, and an interview study. The results indicate that InfoColorizer can provide compelling palette recommendations with adequate flexibility, allowing users to effectively obtain high-quality color design for input infographics with low effort.
Lean‐zinc anode is a promising configuration that can eliminate the trade‐off of energy density and cycle lifetime of zinc metal (Zn0) batteries. However, there are rare investigations of lean‐Zn ...anode designs and it remains a grand change to sustain high zinc reversibility under lean zinc conditions. Herein, a lean‐Zn anode design based on a hierarchical and zincophilic cobalt metal (Co0) nanowire‐decorated carbon host, which is derived from a ZnCo bimetallic organic framework, is reported. Within the lean‐Zn anode, the trace amount of Zn0 acts as a zinc reservoir to make up for any irreversible loss of zinc source upon cycling, while the zincophilic Co0 nanowires can guide uniform zinc nucleation and growth through a lattice matching mechanism. Consequently, high Zn0 reversibility (average Coulomb efficiency of 99.6% for 4250 cycles), low nucleation overpotential (50.8 mV at 1 mA cm−2), and uniform and compact zinc electrodeposition are realized. When coupling the lean‐Zn anode with a Zn‐containing cathode, the full cell delivers high Coulomb efficiency (99.6% for 4250 cycles on average) and a long lifetime of more than 5000 cycles.
A higher lattice matching will contribute to formulating a coherent interface, which can lower the nucleation barrier and promote more even zinc deposition. In this work, a and zincophilic anode structure based on a ZnCo bimetallic organic framework‐derived carbon, which enables the construction of highly reversible, long‐life, and anode‐lean Zn0 full cells when coupling with zinc‐containing cathodes, is reported.
Growth performance and aggressive behavior are important measures in fish aquaculture. So, from the perspectives of food production and fish welfare, it is always valuable to increase growth rate and ...reduce fish aggression efficiently. Physical enrichment has been verified to be a promising method to improve fish welfare. But there is very scarce knowledge about social enrichment, which is an important category of environmental enrichment. In the wild, several fish species often inhabit the same habitat, inevitably experiencing social interactions with each other. From the perspective of nature-based welfare, such social interactions are essential for fish ontogenesis, and deprivation of this social environment may damage fish welfare. Here, we focused on two typical territorial fish species, black rockfish (
Sebastes schlegelii
) and fat greenling (
Hexagrammos otakii
), which are often found to inhabit the same area in the wild, in contrast, traditional fish farms simultaneously rear them with the monoculture mode. And we explored the effects of social enrichment (through introducing different numbers of two fishes into the same environment) on their growth and aggression. The results showed that introducing rockfish as a stimulus significantly increased the growth performance of greenling (especially the medium and high enrichment amounts), but social enrichment did not present such effects on the growth of rockfish. Proper social enrichment also significantly decreased the intraspecies aggression both among rockfish and among greenling. Moreover, greenling expressed significantly more aggressive behavior toward rockfish (i.e., the interspecies aggression from greenling toward rockfish) than in reverse. Finally, the average distribution proportion in central areas and standard metabolic rate of greenling were significantly higher than those of rockfish. These results suggest that proper social enrichment is an effective method to decrease aggression and increase growth of the fat greenling, but this improvement is accompanied by a compromised rockfish welfare. This study will promote the application of environmental enrichment strategy on improving the welfare of specific fish species and provide fundamental information for reducing fish aggression and improving fish growth in aquaculture. Further research is needed to optimize the combinations of fish species for practical applications in aquaculture.
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