AbstractThis paper summarizes the details of a numerical and experimental research program that was conducted to study the debonding of carbon fiber–reinforced polymer (CFRP) patches from cracked ...steel members under fatigue loading. A preliminary numerical model was developed to investigate the influence of patch debonding on the fatigue life of cracked steel elements. Results indicated that altering the shape and increasing the size of the debonded region could change the calculated crack growth rate by up to 54 times. To validate the model, six steel edge–notched tension coupons were patched with CFRP materials and tested under fatigue loading, while full-field strain distributions were monitored using a digital image correlation (DIC)–based measurement system. Based on the experimental results the numerical model was refined to incorporate the interfacial traction-separation behavior. A parametric study was conducted using the refined numerical model. The results indicate that the size and shape of the debonded region, and therefore the fatigue crack propagation rate, are not only dependent on the fatigue detail and the crack length, but also on the maximum magnitude of the applied fatigue load and the properties of the bonded interface.
In this letter, a wideband receive-and-transmit element suitable for linear-to-circular polarization applications is proposed, utilizing a combined field-circuit and conjugate matching design ...approach. The receiver comprises a wideband, linearly polarized kite-shaped dipole, while the transmitter is a wideband, circularly polarized spiral antenna. The two elements' excitation probes are interconnected through a central via, allowing for continuous rotation of the spiral element for phase compensation. To test the proposed design, a 0.24 λ 0 thick transmitarray with 635 elements was constructed, and its performance was assessed. The results indicated a peak gain of 29.3 dBi and peak aperture efficiency of 55.5% within the band. The 1 dB gain bandwidth ranged from 22 to 28.5 GHz, corresponding to a bandwidth of 25.7%.
This study focused on the degradation of the worldwide Non-steroidal Anti-Inflammatory Drug (NSAID) ibuprofen (IBP) by gamma irradiation. Factors affecting IBP degradation efficiency were examined. ...The results showed that IBP concentration decreased with an increasing absorbed dose. When IBP concentration of 28.3mg/L and an absorbed dose of 1.1kGy were chosen, IBP degradation value was 100%. The degradation process of IBP could be depicted by first order reaction kinetics when the absorbed dose was less than 0.9kGy. 0.1% H2O2 and humic acid additives enhanced IBP degradation process, while 0.5% H2O2 additive restrained the degradation of IBP. The additions of CO32−, NO3−, CH3OH and thiourea restrained the degradation process. The pH value affected the IBP degradation. The degradation efficiency was more efficient under acidic condition than in neutral or alkaline media. The solution pH value became lower with increasing absorbed dose after gamma irradiation. High performance liquid chromatography (HPLC) and electrospray ionisation mass spectrometry (ESMS) techniques were employed to identify the IBP derivatives. The mono- and quadric-hydroxylated of IBP and the products due to the oxidation of propanoic acid, and isobutyl substituents of IBP were identified.
► Gamma irradiation could effectively remove ibuprofen in aqueous solution. ► The pH and TOC of IBP solution decreased after gamma irradiation. ► The intermediates of IBP were identified after gamma irradiation.
From 1990, the Agricultural Production Systems sIMulator (APSIM) has grown from a field-focused farming systems framework used by a small number of people, into a large collection of models used by ...thousands of modellers internationally. The software grew to consist of several hundred thousand lines of code in multiple programming languages. This has led to a large, complex software ecosystem that is difficult to maintain. In addition, systems modellers increasingly require software systems that integrate multiple disciplines, can represent evermore complex farming systems, can run on multiple operating systems (desktop, web, mobile), can operate at or be adjusted to multiple temporal and spatial scales (field, farm, region, continent, global) and run faster for larger simulation analyses. This is difficult to achieve in an aging framework.
For these reasons, the APSIM Initiative is building the next generation of APSIM. This manuscript outlines the approach taken and lessons learnt.
•APSIM is an agricultural modelling framework used extensively worldwide.•APSIM Next Generation is a new, modern rewrite of APSIM.•Many lessons have been learnt during this rewrite.•A good software process is important in all model development activities.
An epidemic of severe acute respiratory syndrome (SARS) has been associated with an outbreak of atypical pneumonia originating in Guangdong Province, People's Republic of China. We aimed to identify ...the causative agent in the Guangdong outbreak and describe the emergence and spread of the disease within the province.
We analysed epidemiological information and collected serum and nasopharyngeal aspirates from patients with SARS in Guangdong in mid-February, 2003. We did virus isolation, serological tests, and molecular assays to identify the causative agent.
SARS had been circulating in other cities of Guangdong Province for about 2 months before causing a major outbreak in Guangzhou, the province's capital. A novel coronavirus, SARS coronavirus (CoV), was isolated from specimens from three patients with SARS. Viral antigens were also directly detected in nasopharyngeal aspirates from these patients. 48 of 55 (87%) patients had antibodies to SARS CoV in their convalescent sera. Genetic analysis showed that the SARS CoV isolates from Guangzhou shared the same origin with those in other countries, and had a phylogenetic pathway that matched the spread of SARS to the other parts of the world.
SARS CoV is the infectious agent responsible for the epidemic outbreak of SARS in Guangdong. The virus isolated from patients in Guangdong is the prototype of the SARS CoV in other regions and countries.
Purpose
Lipocalin 2 (LCN2) is a newly recognized bone-derived factor that is important in regulation of energy metabolism. We investigated the correlation of serum LCN2 levels and glycolipid ...metabolism, and body composition in a large cohort of patients with osteogenesis imperfecta (OI).
Methods
A total of 204 children with OI and 66 age- and gender-matched healthy children were included. Circulating levels of LCN2 and osteocalcin were measured by enzyme-linked immunosorbent assay. Serum levels of fasting blood glucose (FBG), triglyceride (TG), total cholesterol (TC), and low- and high-density lipoprotein cholesterol (LDL-C, HDL-C) were measured by automated chemical analyzers. The body composition was measured by dual-energy X-ray absorptiometry. Grip strength and timed-up-and-go (TUG) were tested to evaluate the muscle function.
Results
Serum LCN2 levels were 37.65 ± 23.48 ng/ml in OI children, which was significantly lower than those in healthy control (69.18 ± 35.43 ng/ml,
P
< 0.001). Body mass index (BMI) and serum FBG level were significantly higher and HDL-C levels were lower in OI children than healthy control (all
P
< 0.01). Grip strength was significantly lower (
P
< 0.05), and the TUG was significantly longer in OI patients than healthy control (
P
< 0.05). Serum LCN2 level was negatively correlated to BMI, FBG, HOMA-IR, HOMA-β, total body, and trunk fat mass percentage, and positively correlated to total body and appendicular lean mass percentage (all
P
< 0.05).
Conclusions
Insulin resistance, hyperglycemia, obesity, and muscle dysfunction are common in OI patients. As a novel osteogenic cytokine, LCN2 deficiency may be relevant to disorders of glucose and lipid metabolism, and dysfunction of muscle in OI patients.
This paper presents a first assessment of the global effects of climate-induced sea-level rise on the erosion of sandy beaches, and its consequent impacts in the form of land loss and forced ...migration of people. We consider direct erosion on open sandy coasts and indirect erosion near selected tidal inlets and estuaries, using six global mean sea-level scenarios (in the range of 0.2–0.8m) and six SRES socio-economic development scenarios for the 21st century. Impacts are assessed both without and with adaptation in the form of shore and beach nourishment, based on cost-benefit analysis that includes the benefits of maintaining sandy beaches for tourism. Without nourishment, global land loss would amount to about 6000–17,000km2 during the 21st century, leading to 1.6–5.3million people being forced to migrate and migration costs of US$ 300–1000billion (not discounted). Optimal beach and shore nourishment would cost about US$ 65–220billion (not discounted) during the 21st century and would reduce land loss by 8–14%, forced migration by 56–68% and the cost of forced migration by 77–84% (not discounted). The global share of erodible coast that is nourished increases from about 4% in 2000 to 18–33% in 2100, with beach nourishment being 3–4 times more frequent than shore nourishment, reflecting the importance of tourism benefits. In absolute terms, with or without nourishment, large countries with long shorelines appear to have the largest costs, but in relative terms, small island states appear most impacted by erosion. Considerable uncertainty remains due to the limited availability of basic coastal geomorphological data and models on a global scale. Future work should also further explore the effects of beach tourism, including considering sub-national distributions of beach tourists.
•A first global analysis of erosion of sandy beaches due to sea-level rise•The analysis includes beach and shore nourishment as adaptation options.•6000–17,000km2 land may be lost during the 21st century.•1.6–5.3million people may be forced to migrate during the 21st century.•Nourishment based on benefit-cost analysis reduces forced migration by 56–68%.
The mesh is currently the preferred treatment option for hernia repair surgery. Chronic postoperative inguinal pain (CPIP), lasting more than 3 months after surgery, is a complication that ...significantly impacts patients' quality of life. Currently, there is a lack of evidence-based information describing the incidence and independent predictive factors of chronic pain, posing a serious challenge in clinical practice for devising personalized prevention strategies. Hence, we conducted this systematic review and meta-analysis to investigate the incidence and predictive factors, aiming to provide a reference for developing plans to prevent chronic pain.
We conducted a systematic search of PubMed, Cochrane, Embase, and Web of Science, with the retrieval cutoff date set at December 17, 2022. The included studies underwent assessment using the NOS scale, and subgroup analysis for the incidence was carried out based on different regions.
Ultimately, 18 studies were included, involving 29,466 patients. Meta-analysis showed that the pooled incidence of chronic pain was 17.01% (95%CI 12.78% ~ 21.71%). The incidence was 18.65% (95%CI 13.59% ~ 24.29%) in Europe, 14.70% (95%CI 7.87% ~ 23.17%) in Asia, and 6.04%(95%CI 4.62 ~ 7.64) in North America. Furthermore, We also found that the risk factors for CPIP are younger age OR = 2.261 (95%CI 1.126 ~ 4.549), presence of other postoperative complications OR = 1.849 (95%CI 1.034 ~ 3.305), hernial sac defect < 3 cm OR = 1.370 (95%CI 1.012 ~ 1.853), being female OR = 1.885 (95%CI 1.024 ~ 3.472), postoperative pain OR = 1.553 (95%CI 1.276 ~ 1.889), preoperative pain OR = 2.321 (95%CI 1.354 ~ 3.979), and having a history of ipsilateral inguinal hernia repair OR = 2.706 (95% CI 1.445 ~ 5.069).
The incidence of persistent pain following hernia repair surgery is high in current clinical practice, a concern that should not be overlooked. Stratified assessment tools need to be established for patients experiencing early chronic pain, and personalized follow-up strategies and preventive interventions should be developed for those with potentially high risks. These measures aim to enhance the quality of life for patients after hernia repair.
Early vigour is an important physiological trait to improve establishment, water-use efficiency, and grain yield for wheat. Phenotyping large numbers of lines is challenging due to the fast growth ...and development of wheat seedlings. Here we developed a new photo-based workflow to monitor dynamically the growth and development of the wheat canopy of two wheat lines with a contrasting early vigour trait. Multiview images were taken using a ‘vegetation stress’ camera at 2 d intervals from emergence to the sixth leaf stage. Point clouds were extracted using the Multi-View Stereo and Structure From Motion (MVS-SFM) algorithm, and segmented into individual organs using the Octree method, with leaf midribs fitted using local polynomial function. Finally, phenotypic parameters were calculated from the reconstructed point cloud including: tiller and leaf number, plant height, Haun index, phyllochron, leaf length, angle, and leaf elongation rate. There was good agreement between the observed and estimated leaf length (RMSE=8.6 mm, R²=0.98, n=322) across both lines. Significant contrasts of phenotyping parameters were observed between the two lines and were consistent with manual observations. The early vigour line had fewer tillers (2.4±0.6) and larger leaves (308.0±38.4 mm and 17.1±2.7 mm for leaf length and width, respectively). While the phyllochron of both lines was quite similar, the non-vigorous line had a greater Haun index (more leaves on the main stem) on any date, as the vigorous line had slower development of its first two leaves. The workflow presented in this study provides an efficient method to phenotype individual plants using a low-cost camera (an RGB camera is also suitable) and could be applied in phenotyping for applications in both simulation modelling and breeding. The rapidity and accuracy of this novel method can characterize the results of specific selection criteria (e.g. width of leaf three, number of tillers, rate of leaf appearance) that have been or can now be utilized to breed for early leaf growth and tillering in wheat.
The main goal of this paper is to develop a novel approach for vibration control on a piezoelectric rotating truss structure. This study will analyze the dynamics and control of a flexible structure ...system with multiple degrees of freedom, represented in this research as a clamped–free–free–free truss type plate rotated by motors. The controller has two separate feedback loops for tracking and damping, and the vibration suppression controller is independent of position tracking control. In addition to stabilizing the actual system, the proposed proportional–derivative (PD) control, based on genetic algorithm (GA) to seek the primary optimal control gain, must supplement a fuzzy control law to ensure a stable nonlinear system. This is done by using an intelligent fuzzy controller based on adaptive neuro-fuzzy inference system (ANFIS) with GA tuning to increase the efficiency of fuzzy control. The PD controller, in its assisting role, easily stabilized the linear system. The fuzzy controller rule base was then constructed based on PD performance-related knowledge. Experimental validation for such a structure demonstrates the effectiveness of the proposed controller. The broad range of problems discussed in this research will be found useful in civil, mechanical, and aerospace engineering, for flexible structures with multiple degree-of-freedom motion.
► This paper proposes a novel control methodology for multi-DOF flexible structures. ► The controller has two separate feedback loops for tracking and damping. ► The proposed PD control, based on GA to seek the primary optimal control gain. ► The fuzzy rule base was then constructed based on PD performance-related knowledge. ► The problems discussed in this research will be useful in various engineering area.
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