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Regarding the issue of no standard basis for selecting the load coefficient in the design of high-gears, this paper uses the resistance method to measure the strain at the root of high-gear by building a test rig, and obtains the variation law of tooth root strain under different torques and speeds. Based on the result, the dynamic load coefficient, load distribution coefficient, and load distribution coefficient are calculated according to their definitions, and compared and corrected with the theoretical calculation results.

The effective reproductive number, , is a critical indicator to monitor disease dynamics, inform regional and national policies, and estimate the effectiveness of interventions. It describes the average number of new infections caused by a single infectious person through time. To date, estimates are based on clinical data such as observed cases, hospitalizations, and/or deaths. These estimates are temporarily biased when clinical testing or reporting strategies change. We show that the dynamics of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) RNA in wastewater can be used to estimate in near real time, independent of clinical data and without the associated biases. We collected longitudinal measurements of SARS-CoV-2 RNA in wastewater in Zurich, Switzerland, and San Jose, California, USA. We combined this data with information on the temporal dynamics of shedding (the shedding load distribution) to estimate a time series proportional to the daily COVID-19 infection incidence. We estimated a wastewater-based from this incidence. The method to estimate from wastewater worked robustly on data from two different countries and two wastewater matrices. The resulting estimates were as similar to the estimates from case report data as estimates based on observed cases, hospitalizations, and deaths are among each other. We further provide details on the effect of sampling frequency and the shedding load distribution on the ability to infer . To our knowledge, this is the first time has been estimated from wastewater. This method provides a low-cost, rapid, and independent way to inform SARS-CoV-2 monitoring during the ongoing pandemic and is applicable to future wastewater-based epidemiology targeting other pathogens. https://doi.org/10.1289/EHP10050.

In order to ensure that the load distribution of each distributed power supply is reasonable, we avoid the overload of some distributed power supplies, make full use of all resources, and reduce line losses. A two-layer game operation optimization method for an active distribution network with a high proportion of distributed power is proposed. The output power of the distributed power supply is calculated. The anomaly of the double-layer operation of the active distribution network is identified by the time differential game technique. The optimization index of the two-layer operation stability of the active distribution network is set up. The evaluation function of each optimization index is calculated. The two-layer game operation of an active distribution network with a high proportion of distributed power supply is optimized. The experimental results show that: The output waveform of A phase, B phase, and C phase voltage and current is more stable. The optimization effect is better.

The diamond anvil cell (DAC) is considered one of the dominant devices to generate ultrahigh static pressure. The development of the DAC technique has enabled researchers to explore rich high-pressure science in the multimegabar pressure range. Here, we investigated the behavior of the DAC up to 400 GPa, which is the accepted pressure limit of a conventional DAC. By using a submicrometer synchrotron X-ray beam, double cuppings of the beveled diamond anvils were observed experimentally. Details of pressure loading, distribution, gasket-thickness variation, and diamond anvil deformation were studied to understand the generation of ultrahigh pressures, which may improve the conventional DAC techniques.

The mechanical and acoustic emission characteristics of rock-like materials under non-uniform loads were investigated by means of a self-developed mining-induced stress testing system and acoustic emission monitoring system. In the experiments, the specimens were divided into three regions and different initial vertical stresses and stress loading rates were used to simulate different mining conditions. The mechanical and acoustic emission characteristics between regions were compared, and the effects of different initial vertical stresses and different stress loading rates were analysed. The results showed that the mechanical properties and acoustic emission characteristics of rock-like materials can be notably localized. When the initial vertical stress and stress loading rate are fixed, the peak strength of region B is approximately two times that of region A, and the maximum acoustic emission hit value of region A is approximately 1–2 times that of region B. The effects of the initial vertical stress and stress loading rate on the peck strain, maximum hit value, and occurrence time of the maximum hit are similar in that when either of the former increase, the latter all decrease. However, peck strength will increase with the increase in loading rate and decrease with the increase in initial vertical stress. The acoustic emission hits can be used to analyse the damage in rock material, but the number of acoustic emission hits cannot be used alone to determine the degree of rock damage directly.

In water conservancy, the safe operation of hydraulic cylinders in double-hanging-point radial gate hoists is critical. This study proposes an ANSYS-based FSI method for load checking. SolidWorks models of gates and water are imported into ANSYS Workbench to build an FSI finite element model with hexahedral meshes. Simulations under 5 m/s flow and 1 m opening show max gate deformation (0.02 m), strain (0.0013), and stress (240 MPa), within steel limits. The hydraulic cylinder exhibits 0.2% strain and 180 MPa stress at 5s, well below load limits. The method models environmental parameters and load distribution for safety assessment. High-stiffness materials are recommended to strengthen weak cylinder parts for complex conditions.

Pile-supported embankments are widely used in foundation treatments, owing to their safety, efficient construction, and economy. The soil-arching effect is a key load-transferring mechanism in a pile-supported embankment, and it reduces the even settlement on the embankment surface. In recent years, researchers and engineers have conducted extensive research on the soil-arching phenomenon in pile-supported embankments. This paper reviews relevant studies on the effect of soil arching in pile-supported embankments in order to better understand the mechanism and influencing factors of the distribution of the arching effect. First, the development history of the practice and theory related to pile-supported embankments is discussed. This is followed by a review of theoretical studies on the soil-arching effect, load distribution and soil deformation on pile-supported embankments (with and without geogrid reinforcement), and structures and factors influencing soil arching. The results of these studies are summarized, and finally, topics for future research are suggested, providing references for the design and maintenance of civil infrastructure.

The development of synthetic protocols for the preparation of highly loaded metal nanoparticle-supported catalysts has received a great deal of attention over the last few decades. Independently controlling metal loading, nanoparticle size, distribution, and accessibility has proven challenging because of the clear interdependence between these crucial performance parameters. Here we present a stepwise methodology that, making use of a cobalt-containing metal organic framework as hard template (ZIF-67), allows addressing this long-standing challenge. Condensation of silica in the Co-metal organic framework pore space followed by pyrolysis and subsequent calcination of these composites renders highly loaded cobalt nanocomposites (~ 50 wt.% Co), with cobalt oxide reducibility in the order of 80% and a good particle dispersion, that exhibit high activity, C5 + selectivity and stability in Fischer–Tropsch synthesis. Preparation of supported catalysts with high nanoparticle loading is a considerable synthetic challenge. Here, by using a metal organic framework as sacrificial template, the authors report a cobalt catalyst with a 50% Co loading with superior activity in the C5+ selective production of hydrocarbons from syngas.

A series of work for distributed dynamic load identification is investigated in this paper considering unknown-but-bounded uncertainties in the aircraft structure. To facilitate the analysis, the complicated rudder structure is simplified to a plate structure based on the robust equivalence principle of mechanical property under multi-cases of flight environments. Aiming at the plate structure, a time domain–based model for distributed dynamic load identification is established through the acceleration response measured by sensors. Among them, the spatial distributed load is approximated by Chebyshev orthogonal polynomials at each sampling time, and load boundaries can be calculated by the Taylor-expansion-based uncertain propagation analysis. As keys to improve the reliability of recognition results, the optimization process for sensor placement is constructed by the particle swarm optimization algorithm, taking the robustness evaluation index and sensor distribution index into consideration. The validity and the feasibility of the proposed methodology are demonstrated by several numerical examples, and the results reveal that designer can make a rational tradeoff choice among the cost of sensor placement and the performance of load identification in a systematic framework.

Staphylococcus epidermidis and Staphylococcus aureus are pathogens that can form biofilms on implants and medical devices. Central to biofilm formation is a very tight interaction between microbial surface proteins called adhesins and components of the extracellular matrix of the host. Milles et al. used atomic force microscopy-based single-molecule force spectroscopy combined with steered molecular dynamics to explore how the bond between staphylococcal adhesin SdrG and its target fibrinogen peptide can withstand forces greater than 2 nanonewtons (see the Perspective by Herman-Bausier and Dufrêne). The peptide is confined in a coiled geometry in a deep and rigid pocket through hydrogen bonds between SdrG and the peptide backbone. If pulled, the load is distributed over all hydrogen bonds so that all bonds must be broken at once to break the interaction. Science , this issue p. 1527 ; see also p. 1464 The mechanostability of a staphylococcal adhesin binding to its human target is virtually independent of peptide side chains. High resilience to mechanical stress is key when pathogens adhere to their target and initiate infection. Using atomic force microscopy–based single-molecule force spectroscopy, we explored the mechanical stability of the prototypical staphylococcal adhesin SdrG, which targets a short peptide from human fibrinogen β. Steered molecular dynamics simulations revealed, and single-molecule force spectroscopy experiments confirmed, the mechanism by which this complex withstands forces of over 2 nanonewtons, a regime previously associated with the strength of a covalent bond. The target peptide, confined in a screwlike manner in the binding pocket of SdrG, distributes forces mainly toward the peptide backbone through an intricate hydrogen bond network. Thus, these adhesins can attach to their target with exceptionally resilient mechanostability, virtually independent of peptide side chains.