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Abstract This paper investigates the benefits and challenges of the multi‐MW direct‐drive offshore wind Vernier generators. It is worth noting that the comparison of generator topologies presented in ref. [1] was for the same power level and therefore a reduced machine volume for the surface‐mounted permanent magnet Vernier (SPM‐V) generators. This would mainly impact the capital expenditure (CAPEX) cost between the different investigated machines. Whereas in this paper, the performance is compared for the same machine volume that allows the Vernier generators to produce a much higher energy yield than a conventional SPM generator. As the extra energy yield would be beneficial over the lifetime of the turbine, this will have a bigger impact than the CAPEX cost savings with a reduced machine volume. In addition, a novel Vernier machine with magnets on both the stator and rotor has been proposed to further improve the energy yield. In addition to the basic electromagnetic performance, the levelised cost of energy (LCOE) of the three generator topologies, that is, the conventional SPM, SPM‐V and the proposed Vernier machines, has been compared. The direct‐drive powertrain systems with SPM‐V and the proposed Vernier generators can achieve LCOE of 12.3% and 24% lower than that of the conventional SPM generators, indicating their huge potential as an alternative to reduce the overall cost of energy.

This study aimed to investigate the pharmacokinetics of difloxacin in pigeons following oral (PO), intramuscular (IM), and intravenous (IV) administration. Thirty pigeons were randomly divided into three groups (IM, IV, and PO; n = 10 per group). Difloxacin was administered at 10 mg/kg body weight (BW) via each route. Blood samples were collected at various intervals from 0 to 48 h, and plasma was analyzed for difloxacin concentrations using a validated high-performance liquid chromatography (HPLC) method. Pharmacokinetic parameters were determined using Phoenix software and a non-compartmental analysis (NCA) approach. After PO and IM administration, peak plasma concentrations (Cmax) were observed as 1.81 ± 0.47 and 6.52 ± 1.62 μg/mL, occurring at 2.60 ± 0.97 and 0.63 ± 0.24 h, respectively. Bioavailability (F) was 38.35 % ± 10.45 % for PO and 90.25 % ± 26.14 % for IM administration. Following IV administration, difloxacin was widely distributed, with a volume of distribution (VZ) of 2.52 ± 0.65 L/kg and a steady-state volume of distribution (VSS) of 1.87 ± 0.27 L/kg. Difloxacin exhibited slow elimination, with elimination half-lives (t1/2λzs) of 1.61 ± 0.3, 2.64 ± 0.64, and 4.27 ± 1.14 h after IM, PO, and IV administration, respectively. Based on the AUC/MIC ratios calculated here, the current IM or IV administration at 10 mg/kg BW is effective against bacterial infections with MIC values ≤ 0.1 μg/mL, while the current oral dose (10 mg/kg BW) may be insufficient, particularly for infections caused by pathogens with MIC values exceeding 0.1 μg/mL.

Abstract To achieve precise grasping and spreading of irregular sheet-like soft objects (such as leather) by robots, this study addresses several challenges, including the irregularity of leather edges and the ambiguity of feature recognition points. To tackle these issues, this paper proposes an innovative method that involves alternately grasping the lowest point twice and using planar techniques to effectively spread the leather. We improved the YOLOV8 algorithm by incorporating the BIFPN network structure and the WIOU loss function, and trained a dedicated dataset for the lowest grasping points and planar grasping points, thereby achieving high-precision recognition. Additionally, we determined the optimal posture for grasping the lowest point and constructed an experimental platform, successfully conducting multiple rounds of leather grasping and spreading experiments with a success rate of 72%. Through an in-depth analysis of the failed experiments, this study reveals the limitations of the current methods and provides valuable guidance for future research.

ABSTRACT: This experiment aimed to investigate the in vitro antimicrobial activity of danofloxacin against Escherichia coli (E. coli) isolated from pigeons, as well as the pharmacokinetics of danofloxacin in pigeons following oral (PO), intramuscular (IM), and intravenous (IV) administration. The minimum inhibitory concentration (MIC) of danofloxacin was first determined for 38 clinical E. coli strains using the micro broth dilution method. Subsequently, 30 healthy pigeons were weighed and randomly divided into 3 groups: IM, IV, and PO, with 10 pigeons in each group. Danofloxacin was given at 5 mg/kg body weight (BW) through 3 different routes. Blood was collected, and plasma was separated at various time points from 0 to 48 h. Plasma samples were analyzed for danofloxacin concentrations using a validated HPLC method. Pharmacokinetic analysis was performed using Phoenix software and a noncompartmental analytical (NCA) method. The results indicated that danofloxacin had a strong antibacterial effect on E. coli, with a MIC50 of 0.5 μg/mL. The noncompartmental analysis showed that after PO and IM administration at 5 mg/kg in pigeons, peak plasma concentrations (Cmax) of 0.61 and 1.62 μg/mL were reached at 4.5 and 0.53 h, respectively. The oral and intramuscular bioavailability (F) were 68.08% ± 24.82% and 87.82% ± 25.36%, respectively. Following IV administration, danofloxacin was widely distributed in pigeons, with volume of distribution (VZ) and volume of distribution at steady state (VSS) values of 6.11 ± 2.01 and 4.65 ± 1.62 L/kg, respectively, and was eliminated slowly, with an elimination half-life (t1/2λz) of 6.41 ± 2.15 h. Based on the calculated ratio values of AUC/MIC, the current IV, IM, and PO doses of 5 mg/kg of danofloxacin would be expected to effectively treat pigeons infected with E. coli strains with MIC values equal to or less than 0.5 μg/mL.

ABSTRACT: The current study aimed to investigate the pharmacokinetics of bromhexine hydrochloride in broilers after single intravenous (IV) and oral (PO) administration at 2.5 mg/kg body weight (BW). The trial adopted a randomized, parallel-controlled design, where 20 twelve-wk-old broilers were randomly assigned to either the PO or IV group. Blood samples were collected at predetermined time points, and plasma was further separated for analysis. The bromhexine hydrochloride concentrations in plasma samples were determined using an ultra-performance liquid chromatography-tandem quadrupole mass spectrometry (UPLC-MS/MS) method. Noncompartmental analysis (NCA) using Phoenix software was conducted to analyze the concentration versus time data of bromhexine hydrochloride in every chicken. Subsequently, the main pharmacokinetic parameters between the 2 groups were statistically analyzed using SPSS software. Results from NCA revealed that after oral administration at 2.5 mg/kg BW, bromhexine hydrochloride exhibited slow absorption, reaching an average peak concentration of 32.72 ng/mL at 1.78 h. However, incomplete absorption was observed, with an absolute bioavailability of only 20.06% ± 10.84%. Additionally, bromhexine hydrochloride displayed wide distribution, with a steady-state distribution volume (VSS) of 22.55 ± 13.45 L/kg, and slow elimination, with a clearance (Cl) of 1.52 ± 0.38 L/h/kg. Furthermore, gender effects were assessed on the pharmacokinetics of bromhexine hydrochloride in broilers, revealing better absorption in male broilers compared to females. This disparity may be attributed to the faster blood flow and richer blood volume typically found in male broilers.

Guided by self-determination theory to design an authentic learning environment, we attempted repeated engagement in critical evaluation of evidence to foster accuracy-oriented reasoning and critical thinking in an applied science course for non-STEM undergraduates taught completely online during a 6-week summer term and a 16-week fall term. Student outcomes were measured as indicators of the effectiveness of our pedagogical strategies. Results suggest that student engagement in integration and resolution modes of cognitive presence are associated with students' feelings of autonomy, competence, and relatedness. A positive trend of students moving toward accuracy goals during evidence evaluation was also observed, as students visited both sides of evidence at the same frequency or spent about the same amount of time evaluating both sides of evidence regardless of their voting decision at the end of the course. These findings suggest that scientific literacy among nonscientists may be fostered through repeated, supportive engagement in evidence evaluation.

This paper investigates the influence of single- and double-layer winding structures on the thermal performances of fractional slot permanent magnet (PM) machines with ferrofluid cooling. Ferrofluid is an oil-based liquid with nano-sized ferromagnetic particles and has been injected into the end space of these machines. Owing to the magnetic body force produced by the end-winding leakage flux, the ferrofluid can circulate without the need for external pumps. This enables the establishment of an effective heat transfer path from the end-windings to the housing with water jacket. As a result, the ferrofluid improves the heat transfer rate and hence machine’s overall thermal performance. Multiphysics models accounting for the coupling between electromagnetic (EM) field, fluid dynamics and heat transfer have been built for the investigations. In addition to the dc field simulation as that carried out in literature, these multi-physics models can also simulate the effect of ac field in the end space. The findings indicate that ferrofluid cooling significantly improves the EM and thermal performances for the fractional slot PM machines. In addition, due to different magnetic fields in the end space produced by the single- and double-layer windings, they exhibit different cooling efficiencies. A motorette has been built to validate the simulations.

In the industrial sector, malfunctions of equipment that occur during the production and operation process typically necessitate human intervention to restore normal functionality. However, the question that follows is how to design and optimize the intervention measures based on the modeling of actual intervention scenarios, thereby effectively resolving the faults. In order to address the aforementioned issue, we propose an improved heuristic method based on a causal generative model for the design of optimal intervention, aiming to determine the best intervention measure by analyzing the causal effects among variables. We first construct a dual-layer mapping model grounded in the causal relationships among interrelated variables to generate counterfactual data and assess the effectiveness of intervention measures. Subsequently, given the developed fault intervention scenarios, an adaptive large neighborhood search (ALNS) algorithm employing the expected improvement strategy is utilized to optimize the interventions. This method provides guidance for decision-making during equipment operation and maintenance, and the effectiveness of the proposed model and search strategy have been validated through tests on the synthetic datasets and satellite attitude control system dataset.

Abstract Gas hydrates provide alternative solutions for gas storage & transportation and gas separation. However, slow formation rate of clathrate hydrate has hindered their commercial development. Here we report a form of porous ice containing an unfrozen solution layer of sodium dodecyl sulfate, here named active ice, which can significantly accelerate gas hydrate formation while generating little heat. It can be readily produced via forming gas hydrates with water containing very low dosage (0.06 wt% or 600 ppm) of surfactant like sodium dodecyl sulfate and dissociating it below the ice point, or by simply mixing ice powder or natural snow with the surfactant. We prove that the active ice can rapidly store gas with high storage capacity up to 185 V g V w −1 with heat release of ~18 kJ mol−1 CH4 and the active ice can be easily regenerated by depressurization below the ice point. The active ice undergoes cyclic ice−hydrate−ice phase changes during gas uptake/release, thus removing most critical drawbacks of hydrate-based technologies. Our work provides a green and economic approach to gas storage and gas separation and paves the way to industrial application of hydrate-based technologies.

ABSTRACT: This study aimed to compare the residue depletion of gamithromycin in yellow-feather and white-feather broilers, using Sanhuang and Arbor Acres chickens as typical examples, respectively. Each breed (54 chickens) received a single subcutaneous dose of gamithromycin at 7.5 mg/kg bodyweight (BW). Tissues, including muscle, skin + fat, liver, kidney, and injection site, were collected at 6 h, 3, 5, 7, 10, 14, 21, 28, and 35 d postdrug administration. Gamithromycin concentrations in these tissues were determined using ultra‐performance liquid chromatography–tandem mass spectrometry (UPLC‐MS/MS). The kinetics of gamithromycin were analyzed in different tissues using a noncompartmental method in the Phoenix software. Differences were observed in gamithromycin concentrations and kinetic characteristics in both breeds of chickens, with higher residue concentrations and longer residue times found in yellow-feathered broilers. In Sanhuang broilers, the elimination rates of gamithromycin followed this order: injection site > muscle > liver > kidney > skin + fat. The corresponding elimination half-lives (t1/2λzs) in these samples were 1.22, 1.30, 1.71, 2.04, and 2.52 d, respectively. In contrast, in Arbor Acres broilers, a different order was noted: muscle > injection site > kidney > liver > skin + fat, with corresponding t1/2λzs of 1, 1.23, 1.88, 1.93, and 2.21 d, respectively. These differences may be related to variations in pigments in various tissues of chickens of the 2 breeds. However, further investigations are warranted to discern the underlying reasons.

ABSTRACT: This study aimed to investigate the in vitro antibacterial activity of danofloxacin against Escherichia coli isolated from Gushi chickens, as well as the tissue distribution and residue depletion of danofloxacin in Gushi chickens following multiple oral administration. A total of 42 clinical E. coli strains were isolated from the cloaca of locally farmed Gushi chickens between August and October 2023. Then the minimum inhibitory concentration (MIC) of danofloxacin against these isolates was determined by broth microdilution method. Additionally, 42 healthy Gushi chickens were randomly divided into 6 groups, and danofloxacin was orally administered at a dose of 5 mg/kg body weight (BW) for 3 consecutive days. Plasma, intestinal content, and tissue samples, including muscle, skin + fat, liver, kidney, lung, and intestine, were collected at 4, 12, 24, 48, 72, and 120 h after the last administration. Danofloxacin concentrations in all samples were determined using a high-performance liquid chromatography (HPLC) method. The average concentration vs. time data were then subjected to noncompartmental analysis using Phoenix software, and withdrawal periods for danofloxacin in Gushi chickens were further determined with WT1.4 software, setting a 95% confidence interval. Results indicated a notable inhibitory effect of danofloxacin on E. coli, with an MIC50 of 0.5 μg/mL. Additionally, danofloxacin exhibited widespread distribution in Gushi chickens, detectable in all collected samples. Among all tissues, the liver exhibited the highest concentration, followed by the intestine. Even on the fifth day postadministration, danofloxacin persisted in skin + fat, liver, and lung. The elimination half-lives (t1/2λzs) of danofloxacin varied across samples: skin + fat (47.87 h), lung (30.61 h), liver (22.07 h), plasma (16.05 h), muscle (12.53 h), intestine (9.83 h), and kidney (6.34 h). Considering residue depletion and the maximum residue limit (MRL) of danofloxacin in poultry set by Chinese regulatory authorities, withdrawal periods for the kidney, muscle, liver, and skin + fat were determined as 1.03, 1.38, 3.34, and 5.85 d, respectively, rounded to a final withdrawal time of 6 d.

Abstract A general analytical model is developed in a concise block matrix form for surface‐mounted permanent magnet (SPM) machines with series‐parallel coil connections under inter‐turn short circuit (ITSC) fault. In the model, branch currents are used as state variables and inductances of different series‐parallel coil connections are calculated using an analytical method, namely winding function approach (WFA) together with slot permeance method. Based on the characteristics of the calculated inductances and the developed fault model, the multiphase Clarke transformation has been proposed to simplify the fault model. In the process of model simplification, the healthy machine model using branch currents as state variables have been proven to be equivalent to that using 3‐phase currents as state variables. The proposed fault models of a 3kW 96‐slot 32‐pole SPM machine with different series‐parallel coil connections have been built in Matlab/Simulink and validated by time‐stepping 2D FE simulations. Simulation results show that different series‐parallel coil connections have little influence on the amplitude of the ITSC current. Finally, a small scale 24‐slot 8‐pole SPM machine prototype has been built to further validate the accuracy of the proposed fault model.

With the increase of data storage and the improvement of computing power,using observational data to infer time series causality has become a novel approach.Based on the properties and research status of time series causal inference,five observational data-based methods were induced,including Granger causal analysis,information theory-based method,causal network structure learning algorithm,structural causal model-based method and method based on nonlinear state-space model.Then we briefly introduced typical applications in economics and finance,medical science and biology,earth system science and other engineering fields.Further,we compared the advantages and disadvantages and analyzed the ways for improvement of the five methods according to the focus and difficulties of time series causal inference.Finally,we looked into the future research directions.

ABSTRACT: This study investigates the combined effects of chitooligosaccharide (COS) and florfenicol (FLO) on the inhibition of Escherichia coli in vitro, as well as the pharmacokinetic interactions between these compounds in healthy chickens. The minimum inhibitory concentration (MIC) of COS and FLO alone and the fractional inhibitory concentration index (FICI) after combined treatment were determined using the broth microdilution method and checkerboard method, respectively. Additionally, we evaluated the pharmacokinetic interactions between the 2 types of COS and FLO in healthy chickens. Thirty chickens were randomly divided into 3 groups: Florfenicol group (30 mg/kg), COS J85 group (COS J85 20 mg/kg + florfenicol 30 mg/kg), COS H85 group (COS H85 20 mg/kg + florfenicol 30 mg/kg). Either FLO or COS was orally administered by gavage. The concentrations of FLO in chicken plasma were measured at different time points after the drug withdrawal using high-performance liquid chromatography (HPLC), and pharmacokinetic parameters were calculated by a compartmental method. The results showed that COS J85 and COS H85, when combined with FLO, had FICI values of 0.1875 to 0.75 and 0.3125 to 1, respectively, indicating good synergistic or additive effects against Escherichia coli. The pharmacokinetics of FLO alone and in combination with COS followed a 1-compartment model with first-order absorption and elimination. Furthermore, the pharmacokinetic analysis revealed that the elimination half-life (t1/2ke) of florfenicol was significantly increased in the COS H85 group compared to oral administration of florfenicol alone (P < 0.05). Other pharmacokinetic parameters did not show significant changes (P > 0.05), except between the 2 combined treatment groups, where statistical differences were observed for various parameters, excluding the area under the concentration-time curve from the time of dosing to infinity (AUC) and peak concentration (Cmax).