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Objectives: To assess the efficacy and tolerability of iGlarLixi—a novel, fixed-ratio, soluble combination of insulin glargine and lixisenatide—for the treatment of type 2 diabetes (T2D). Methods: The PubMed, Embase, Cochrane Library and ClinicalTrials.gov databases were searched from inception to November 15, 2023 to identify randomized controlled trials (RCTs) comparing iGlarLixi with a placebo or any other antidiabetic agent in adults with T2D. Risk ratios (RRs) and mean differences (MDs) with 95% confidence intervals (CIs) were calculated to evaluate the outcomes. Results: A total of 10 trials enrolling 6071 T2D patients were included. Compared with placebos or other antidiabetic agents, iGlarLixi exerted beneficial effects on changes in HbA1c, the percentage of patients who achieved an HbA1c < 7%, the percentage of patients who achieved an HbA1c < 6.5%, the percentage of patients who achieved an HbA1c < 7.0% without weight gain and/or without severe or blood glucose-confirmed hypoglycemic episodes, changes in fasting plasma glucose, and changes in self-measured plasma glucose. Regarding safety, iGlarLixi did not increase the incidence of severe hypoglycemia or serious adverse events but did increase the incidence of gastrointestinal adverse events, symptomatic hypoglycemia, and adverse events (e.g., nausea, vomiting, diarrhea). Conclusions: iGlarLixi showed improved efficacy and safety in patients with T2D. Additional large, multicenter RCTs are warranted to obtain deeper insights into the efficacy and safety of iGlarLixi, thereby providing guidance for clinical treatment decisions. [ABSTRACT FROM AUTHOR]

This study aimed to explore physicians' and pharmacists' knowledge, attitudes, and practice (KAP) regarding the prevention and treatment of cardiovascular toxicity associated with cancer treatment. A multicenter cross-sectional study included physicians and pharmacists between April 2023 and June 2023. The study included 918 participants (514 physicians and 404 pharmacists). The average scores of knowledge, attitudes, and practice were 11.6 ± 3.39, 24.7 ± 2.6, and 26.3 ± 6.8 points. Sufficient knowledge was significantly associated with age ≥ 41 years (odds ratio (OR) = 2.745, 95% confidence interval (CI) 1.086–6.941, P = 0.033), male (OR = 2.745, 95% CI 1.150–2.223, P = 0.005), bachelor's degree (OR = 0.084, 95% CI 0.013–0.533, P = 0.009), master's degree and above (OR = 0.096, 95% CI 0.015–0.609, P = 0.013), physician occupation (OR = 7.601, 95% CI 1.337–43.207, P = 0.022), pharmacy department (OR = 18.858, 95% CI 3.245–109.57, P = 0.001), oncology department (OR = 4.304, 95% CI 2.426–7.634, P < 0.001), cardiology department (OR = 3.001, 95% CI 1.387–6.492, P = 0.005), hospitals located in Eastern China (OR = 1.957, 95% CI 1.120–3.418, P = 0.018), and hospitals located in Western China (OR = 3.137, 95% CI 1.783–5.518, P < 0.001). Positive attitudes were significantly associated with a senior professional title (OR = 2.989, 95% CI 1.124–7.954, P = 0.028) and hospitals located in Eastern China (OR = 0.424, 95% CI 0.257–0.698, P = 0.001), Western China (OR = 0.231, 95% CI 0.136–0.394, P < 0.001), and Southern China (OR = 0.341, 95% CI 0.198–0.587, P < 0.001). Proactive practice was significantly associated with male (OR = 1.414, 95% CI 1.029–1.943, P = 0.033), senior professional title (OR = 3.838, 95% CI 1.176–12.524, P = 0.026), oncology department (OR = 3.827, 95% CI 2.336–6.272, P < 0.001), and cardiology department (OR = 2.428, 95% CI 1.263–4.669, P = 0.008). Both physicians and pharmacists had positive attitudes toward the prevention and treatment of cardiovascular toxicity associated with cancer treatment, while their knowledge and practice were not as proactive. [ABSTRACT FROM AUTHOR]

The use of agricultural films, pesticides, and fertilizers has increased in China, leading to the degradation of the agricultural ecological environment. Based on the panel data of 30 provinces in China from 2010 to 2021, this paper takes agricultural film usage as the threshold variable to study the impact of pesticide and fertilizer usage on agricultural development. The research results show that a single threshold effect of agricultural film usage is significant. When agricultural film usage is both a core and threshold variable, that is lower than the threshold value, every 1% increase in agricultural film usage will reduce agricultural output value by 0.9862%, and the impact is significant. When agricultural film usage crosses the threshold value, every 1% increase in agricultural film usage will increase agricultural output value by 1.1843%, and the impact is significant. When pesticide usage is the core variable, regardless of whether agricultural film usage is below or above the threshold, pesticide usage promotes agricultural development. Its impact is significant. When fertilizer input is a core variable, regardless of whether agricultural film usage is below or above the threshold, the use of fertilizers hinders agricultural development. The impact of fertilizer input on agricultural development is significant. Through empirical testing, this paper explores the deep relationship between agricultural film usage, pesticide usage and fertilizer input on agricultural development. These can effectively allocate agricultural production factors, transform the mode of agricultural economic growth, achieve the coordinated development of the ecological environment and agricultural economy and provide data support for the formulation of agricultural green development policies. [ABSTRACT FROM AUTHOR]

Based on balanced panel data from 30 provinces and cities (excluding Hong Kong, Macao, Taiwan, and the Tibet Autonomous Region) from 2016 to 2020, this article empirically analyses the spatial effect of green credit (GD) on air quality index (AQI) and the regulatory mechanism between them and explores the differences in the impact of GD on AQI by dividing China into regions in terms of geographical distribution, financial development level, and air quality level. The empirical results found that AQI depends on significant spatial characteristics. GD has a significant inverted U-shaped impact on AQI and is currently at the stage of suppressing air quality. The inverted U-shaped impact is more remarkable in the eastern region, in areas with poor financial development, in areas with poor air quality and GD has entered the stage of promoting air quality levels in the eastern regions, and in areas with good financial development. Environmental regulation has a negative moderating effect on the relationship between GD and AQI, which is less pronounced in eastern regions, in areas with poorly financial development, and in areas with better air quality. [ABSTRACT FROM AUTHOR]

Alternative splicing is an important step in eukaryotic mRNA pre-processing which increases the complexity of gene expression programs, but is frequently altered in disease. Previous work on the regulation of alternative splicing has demonstrated that splicing is controlled by RNA-binding proteins (RBPs) and by epigenetic DNA/histone modifications which affect splicing by changing the speed of polymerase-mediated pre-mRNA transcription. The interplay of these different layers of splicing regulation is poorly understood. In this paper, we derived mathematical models describing how splicing decisions in a three-exon gene are made by combinatorial spliceosome binding to splice sites during ongoing transcription. We additionally take into account the effect of a regulatory RBP and find that the RBP binding position within the sequence is a key determinant of how RNA polymerase velocity affects splicing. Based on these results, we explain paradoxical observations in the experimental literature and further derive rules explaining why the same RBP can act as inhibitor or activator of cassette exon inclusion depending on its binding position. Finally, we derive a stochastic description of co-transcriptional splicing regulation at the single-cell level and show that splicing outcomes show little noise and follow a binomial distribution despite complex regulation by a multitude of factors. Taken together, our simulations demonstrate the robustness of splicing outcomes and reveal that quantitative insights into kinetic competition of co-transcriptional events are required to fully understand this important mechanism of gene expression diversity. [ABSTRACT FROM AUTHOR]

As the division of labor in global industrial value chains deepens, the embedded relationships and carbon emission relationships among countries become more complex. First, calculate the embedding indices of forward and backward global industrial value chains and establish the Multi-Regional Input Output (MRIO) model to calculate trade-implied carbon emissions. Second, construct higher-order weighted networks characterized by hypergraphs from 2000 to 2018, and calculate a high-dimensional vector of characteristic indicators based on apices and hyperedges. Finally, time exponential random graph models are constructed using maximum pseudo-likelihood estimation and Markov Monte Carlo simulation methods to dynamically observe the evolution of the impact mechanism of forward and backward industrial value chains embedded in trade-implied carbon emissions networks. The conclusions obtained are as follows: First, most countries tend to develop backward industries when embedded in global industrial value chains. Second, based on the Global Industry Classification Standard (GICS) criteria, industries deeply embedded in global forward value chains are mainly concentrated in materials and utilities, etc., while industries more deeply embedded in global backward value chains are mainly concentrated in consumer discretionary and real estate industries, etc. Third, "carbon transfer" and "carbon leakage" gradually widen the gap between developed and developing countries, both on the production and consumption sides. Fourth, we decompose the factors influencing industrial carbon emissions into carbon intensity effects, industrial structure effects, and output scale effects and analyze their influence mechanisms. Fifth, for countries with different carbon flow attributes, their forward and backward embedded global industrial value chains have different effects on trade-implied carbon emissions. Sixth, the effective paths of trade that lead to a reduction in carbon emissions are different for countries with different carbon flow characteristics. [ABSTRACT FROM AUTHOR]

A marked elevation of TLR4 was observed in various organs of septic mice. The mechanism of TLR4 in intestinal epithelial cell damage in sepsis remains unclear. CLP mice models were used to assess the role of TLR4 in intestinal Paneth cell damage by histological, polymerase chain reaction, western-blot analyses. The ileal expression of TLR4 was increased by more than five-fold after CLP. CLP significantly increased 7-day mortality and was associated with a higher murine sepsis score (MSS), closely related with increased TLR4 expression. Histological staining revealed that a reduced number of Paneth cells, accompanied by reduced lysozyme and defensin alpha 5(DEF-5) expression as detected by PCR. Of note, the expression levels of ATF6, XBP1 and CHOP increased in the ileal of the sepsis group. Meanwhile, the uncleaved p90 ATF6 was markedly reduced and cleaved p50 ATF6 was increased in the sepsis group. Intriguingly, The TAK-242 had improved intestinal mucosal injury, reduced the expression of ATF6, XBP1 and CHOP and relieved the cleavage of ATF6. We found that increased the expression level of TLR4 in the ileal of CLP mice promoted the depletion of Paneth cell and reduced LYZ and DEF-5 expression. Furthermore, our findings suggested that TLR4-mediated the hyperactivation of ER stress, via activating the ATF6/CHOP pathway, might be one of the mechanisms associated with Paneth cells loss and dysfunction during intestinal barrier impairment of sepsis. [ABSTRACT FROM AUTHOR]

Eukaryotic circadian clocks are based on self-sustaining, cell-autonomous oscillatory feedback loops that can synchronize with the environment via recurrent stimuli (zeitgebers) such as light. The components of biological clocks and their network interactions are becoming increasingly known, calling for a quantitative understanding of their role for clock function. However, the development of data-driven mathematical clock models has remained limited by the lack of sufficiently accurate data. Here we present a comprehensive model of the circadian clock of Neurospora crassa that describe free-running oscillations in constant darkness and entrainment in light-dark cycles. To parameterize the model, we measured high-resolution time courses of luciferase reporters of morning and evening specific clock genes in WT and a mutant strain. Fitting the model to such comprehensive data allowed estimating parameters governing circadian phase, period length and amplitude, and the response of genes to light cues. Our model suggests that functional maturation of the core clock protein Frequency causes a delay in negative feedback that is critical for generating circadian rhythms. Author summary: Circadian rhythms are endogenous autonomous clocks that emancipate daily rhythms in physiology and behavior. Lately, a large body of research has contributed to our understanding of clocks' genetic and mechanistic basis across kingdoms of life, i.e., mammals, fungi, plants, and bacteria. Several mathematical models have made key contributions to our current understanding of the design principles of the Neurospora crassa circadian clock and conditions for self-sustained oscillations. However, previous models uncovered and described the principle properties of the clock in generic manner due to a lack of experimental data. In this study, we developed a mathematical model based on systems of differential equations to describe the core clock components and estimated model parameters from luciferase data that capture experimental observations. We demonstrate the model predictive control simulation emphasizing the importance of functional maturation of the core clock protein Frequency in generating circadian rhythms. [ABSTRACT FROM AUTHOR]

Hematopoietic stem cells (HSCs) produce highly diverse cell lineages. Here, we chart native lineage pathways emanating from HSCs and define their physiological regulation by computationally integrating experimental approaches for fate mapping, mitotic tracking, and single-cell RNA sequencing. We find that lineages begin to split when cells leave the tip HSC population, marked by high Sca-1 and CD201 expression. Downstream, HSCs either retain high Sca-1 expression and the ability to generate lymphocytes, or irreversibly reduce Sca-1 level and enter into erythro-myelopoiesis or thrombopoiesis. Thrombopoiesis is the sum of two pathways that make comparable contributions in steady state, a long route via multipotent progenitors and CD48hi megakaryocyte progenitors (MkPs), and a short route from HSCs to developmentally distinct CD48−/lo MkPs. Enhanced thrombopoietin signaling differentially accelerates the short pathway, enabling a rapid response to increasing demand. In sum, we provide a blueprint for mapping physiological differentiation fluxes from HSCs and decipher two functionally distinct pathways of native thrombopoiesis. Hematopoietic stem cells produce diverse cell lineages. Here, the authors apply single-cell RNA-seq, computational integration of non-perturbative approaches for fate-mapping, and mitotic tracking to chart lineage decisions in native hematopoiesis and identify megakaryocyte progenitors that directly link HSCs to megakaryocytes. [ABSTRACT FROM AUTHOR]

With the rapid development of industrialization and urbanization in China, the ecological environment has been damaged, especially the air quality, which has negatively impacted the productivity and lives of residents. China has taken various measures to improve air quality, and industrial upgrading is one of these measures. This article uses urban and provincial data from 2015 to 2018 and a multilevel growth model to study how industrial upgrading can improve air quality. The following conclusions are drawn through empirical analysis. If industrial upgrading is not considered, with time, air quality will gradually deteriorate. However, once the country adopts strategic measures for industrial upgrading, the combined effect of industrial upgrading and time will improve air quality. Industrial upgrading and industrial restructuring jointly reduce air pollution and have a significant impact on the improvement of air quality. Company goals for economic profit and survival will eventually lead to overall industrial upgrades that have little effect on air improvement. According to the empirical results, this paper puts forward some suggestions to improve the air quality. [ABSTRACT FROM AUTHOR]

The average annual growth rate of China's waste emissions from 2007 to 2017 was 2.3%. The main pollutants in the wastewater are chemical oxygen demand, ammonia nitrogen, total ammonia, total phosphorus, and so on which pollute groundwater and destroy ecosystems. Poor water quality reduces the edible value of agricultural products and has an impact on human health. Based on the panel data of 31 provinces in China from 2007 to 2017, this paper uses a dynamic spatial panel lag model to study the impact of China's water pollution on agricultural economic growth. The results show that the impact of China's water pollution on agricultural economic growth is significant. If the intensity of wastewater discharge is taken as an input factor in the process of agricultural production, the growth of agricultural economy tends to decline with the increase of water pollution. In the effect analysis, the short-term and long-term effects are significant. The absolute value of the long-term total effect is far greater than the short-term total effect, indicating that the inhibitory effect of water pollution on agricultural economic growth is more obvious. The cumulative effect of water pollution on agricultural economic growth continues to expand, resulting in more and more economic losses. The central and local governments should take various measures to reduce water pollution, guide the green development of agriculture, and increase farmers' income to realize the rural revitalization plan. [ABSTRACT FROM AUTHOR]

Haze pollution in China is very serious and has become the source of mortality, affecting the health and lives of residents. The Chinese government adopts different policy measures to reduce haze pollution. The impact of different types of environmental regulations on haze pollution has become a hot topic for academics and government departments. Based on panel data from 2005–2017, this paper studies the effect of different types of environmental regulations on haze pollution in 30 provinces of China using a panel quantile model. The results show that when haze pollution changes from a low quantile to a high quantile, the marginal impact of command-and-control environmental regulation on haze pollution changes from 0.122 to -0.332. Command-and-control environmental regulation can reduce haze pollution, but its impact is not significant. The main reason for this finding is that environmental law enforcement is not strict. The marginal impact of economically restrained environmental regulation on haze pollution changes from -14.389 to 49.939. Economically restrained environmental regulation can reduce haze pollution in low quantiles, but not in high quantiles. The collection of sewage charges fees is far less than the total profit, which has no deterrent effect on enterprises. The marginal impact of public participation in environmental regulation on haze pollution changes from 0.154 to -0.002. Public participation in environmental regulation cannot reduce haze pollution in low quantiles, but can in high quantiles; however its impact becomes insignificant. This study reveals the quantile-based discrepancy in the effect of environmental regulation on haze pollution, and offers a new perspective for research on the effects of environmental regulation. [ABSTRACT FROM AUTHOR]

Using the panel data of China's provinces from 2005 to 2016, the paper adopts the ultra-efficiency model to measure the green economy efficiency of each province. Then, the paper used the panel threshold model to study the impact of science and technological input on the green economy efficiency with the energy consumption intensity as a threshold variable. The results show that the green economy efficiency in China's provinces is low and is in a downward trend. When the energy consumption intensity is the threshold variable, the single-threshold effect is significant. When the energy consumption intensity is lower than the threshold value, the impact of science and technological input on green economic efficiency is not significant, and the energy consumption intensity has a significant impact on green economic efficiency with science and technological input and energy consumption intensity as the core explanatory variables and with energy consumption intensity as the threshold variable. When the energy consumption intensity crosses the threshold value, the impact of science and technological input and energy consumption intensity on green economic efficiency becomes significant. According to the above empirical results, this paper proposes corresponding countermeasures and suggestions. [ABSTRACT FROM AUTHOR]

We report the synergistic adsorption and activation of CO2 by using magnesium oxide anchored into a hollow carbon sphere (MgO/HCS) as an efficient catalyst for electrochemical reduction of CO2 (ERC). The MgO/HCS catalyst exhibits a high selectivity for CO production with a faradaic efficiency of 81.7% at −1.0 V VS. RHE and a partial current density (PCD) of 16.7 mA cm−2 in aqueous electrolyte. [ABSTRACT FROM AUTHOR]

The problem of real-time imaging in synthetic aperture radar (SAR) system is addressed here. Sub-aperture processing algorithm is usually used in the engineering applications. However, high azimuth sidelobes and edge aliasing problem usually occur in conventional sub-aperture algorithm, which degenerates the quality of the SAR image. To solve this problem, the reason for high azimuth sidelobes and edge aliasing problem is analysed, and a modified sub-aperture processing algorithm is proposed. The proposed algorithm minimises the effect of the phase discontinuity to improve the SAR image quality. Therefore, the azimuth sidelobes can be improved, and the edge aliasing phenomenon will be eliminated. Real measured airborne SAR datasets demonstrate the effectiveness of the proposed algorithm. [ABSTRACT FROM AUTHOR]

Through panel data for every province in China from 2006 to 2016, this paper studies the impact of the efficiency of science and technological services and the level of economic development on environmental governance, with the efficiency of science and technological services as the threshold variables. The results of the research indicate that the efficiency of science and technological services in China's provinces is low, while the regional gap is expanding. When the efficiency of science and technological services is the threshold variable, single threshold results are significant. When the efficiency of science and technological services is the threshold variable and when the efficiency of science and technological services is lower than the threshold value, there is a significant impact on environmental governance. If the efficiency of science and technological services crosses the threshold value, the impact of science and technological service efficiency on environmental governance becomes insignificant. For the level of economic development, it is a core explanatory variable and has a significant impact on environmental governance only when the efficiency of science and technological services is below the threshold value. According to the empirical results, this paper proposes corresponding countermeasures and suggestions. [ABSTRACT FROM AUTHOR]

The main adverse effect of tyrosine kinase inhibitors, such as sunitinib, is cardiac contractile dysfunction; however, the molecular mechanisms of this effect remain largely obscure. MicroRNAs (miRNAs) are key regulatory factors in both cardiovascular diseases and the tyrosine kinase pathway. Therefore, we analyzed the differential expression of miRNAs in the myocardium in mice after exposure to sunitinib using miRNA microarray. A significant downregulation of miR-146a was observed in the myocardium of sunitinib-treated mice, along with a 20% decrease in left ventricle ejection fraction (LVEF). The downregulation of miR-146a was further validated by RT-qPCR. Among the potential targets of miR-146a, we focused on Pln and Ank2 , which are closely related to cardiac contractile dysfunction. Results of luciferase reporter assay confirmed that miR-146a directly targeted the 3′ untranslated region of Pln and Ank2. Significant upregulation of PLN and ANK2 at the mRNA and protein levels was observed in the myocardium of sunitinib-treated mice. Cardiac-specific overexpression of miR-146a prevented the deteriorate effect of SNT on calcium transients, thereby alleviating the decreased contractility of human induced pluripotent stem cell-derived cardiomyocytes (hiPSC-CMs). SiRNA knockdown of PLN or ANK2 prevented sunitinib-induced suppression of contractility in hiPSC-CMs. Therefore, our in vivo and in vitro results showed that sunitinib downregulated miR-146a, which contributes to cardiac contractile dysfunction by regulating the downstream targets PLN and ANK2, and that upregulation of miR-146a alleviated the inhibitory effect of SNT on cardiac contractility. Thus, miR-146a could be a useful protective agent against sunitinib-induced cardiac dysfunction. [ABSTRACT FROM AUTHOR]

Sunitinib (SNT) is a multi-targeted receptor tyrosine kinase inhibitor that has been approved by the FDA for cancer therapy. However, its cardiotoxicity has limited the clinical applicability with no effective therapeutic approach available. As a broadband kinase inhibitor, the function of several kinases that are essential to cardiac function might also be affected by SNT, such as calmodulin-dependent protein kinase (CaMKII), cyclic-AMP-dependent protein kinases (PKA), AMP-activated protein kinase (AMPK), and phosphoinositide 3 kinase (PI3K). In this study, we investigated whether SNT-induced cardiotoxicity could be prevented by blocking SNT-induced alteration in the corresponding signaling pathways. In human induced pluripotent stem cell-derived cardiomyocytes, SNT (0.5–20 µmol/L) inhibited contractility of cardiomyocytes in a concentration-dependent manner, and the inhibitory effect was prevented either by PIP3 (1 µmol/L) application or PI3K overexpression. On the contrary, the CaMKII inhibitor KN-93 (50 nmol/L), PKA inhibitor H89 (1 µmol/L), and AMPK activators metformin (2 mmol/L) and 5-aminoimidazole-4-carboxamide 1-b-d-ribofuranoside (2 mmol/L) presented negligible effects. Oral SNT administration (40 mg/kg/day) in mice progressively decreased the PI3K activity and cardiac function in 2 weeks with a significant decrease in the expression and activity of Cav1.2 and SERCA. Cardiac-specific PI3K overexpression through adeno-associated virus 9-mediated gene delivery in mice prevented SNT-induced reduction in cardiac function, calcium transient, calcium current, and Cav1.2 expression. In summary, our data indicate that increased PI3K activity is protective against SNT-induced calcium mishandling and contractile dysfunction. Cardiac-specific PI3K activation could be an effective therapeutic approach to treat SNT cardiotoxicity in patients with cancer. [ABSTRACT FROM AUTHOR]

Drug-induced long QT increases the risk of ventricular tachyarrhythmia known as torsades de pointes (TdP). Many biomarkers have been used to predict TdP. At present, however, there are few biomarkers for arrhythmias induced by QT-shortening drugs. The objective of the present study was to identify the best biomarkers for predicting arrhythmias caused by the 4 potassium channel openers ICA-105574, NS-1643, R-L3, and pinacidil. Our results showed that, at higher concentrations, all 4 potassium channel openers induced ventricular tachycardia (VT) and ventricular fibrillation (VF) in Langendorff-perfused guinea pig hearts, but not in rabbit hearts. The electrocardiography parameters were measured including QT/QTc, JT peak, Tp-e interval, JT area, short-term beat-to-beat QT interval variability (STV), and index of cardiac electrophysiological balance (iCEB). We found that the potassium channel openers at test concentrations shortened the QT/QTc and the JT peak interval and increased the JT area. Nevertheless, even at proarrhythmic concentrations, they did not always change STV, Tp-e, or iCEB. Receiver operating characteristic curve analysis showed that the JT peak interval representing the early repolarization phase and the JT area reflecting the dispersion of ventricular repolarization were the best predictors of VT/VF. Action potential recordings in guinea pig papillary muscle revealed that except for pinacidil, the potassium channel openers shortened APD30 in a concentration-dependent manner. They also evoked early or delayed afterdepolarizations at fast pacing rates. Patch-clamp recordings in guinea pig ventricular cardiomyocytes showed that the potassium channel openers enhanced the total outward currents during the early phase of action potential repolarization, especially at proarrhythmic concentrations. We concluded that the JT peak interval and the JT area are surrogate biomarkers identifying the risk of proarrhythmia associated with the administration of QT-shortening agents. The acceleration of early-phase repolarization and the increased dispersion of ventricular repolarization may contribute to the occurrence of arrhythmias. [ABSTRACT FROM AUTHOR]

Steelmaking–continuous casting is a complex process. The method of selecting a ladle, which also functions as a storage device, follows a specific process of the production plan. In ladle matching, several ladle attributes are considered. However, matching objectives are difficult to achieve simultaneously. Different molten steel properties have contributed to the complexity of matching constraints, and, thus, matching optimization is regarded a multiconflict goal problem. In the process of optimization, the first-order rule learning method is first used to extract key ladle attributes (performance indicators), including highest temperature, usage frequency, lowest-level material, and outlet. On the basis of a number of indicators, such as ladle temperature, quantity, material, and usage frequency, as well as skateboard quantity, the ladle matching model is established. Second, the rule of ladle selection is determined by the method of least-generalization rule learning. Third, a simulation experiment is carried out according to various scheduling order strategies and matching priority combinations. Finally, the heuristic ladle matching method based on the rule priority (RP) is determined for possible industrial applications. Results show that the accuracy of ladle selection can be improved. In particular, the numbers of ladles and maintenance times are reduced. Consequently, furnace production efficiency is also enhanced. [ABSTRACT FROM AUTHOR]

A new approach for simulating three-dimensional (3D) bulk metal forming processes is proposed by combining element-free Galerkin method (EFGM) with the flow theory of 3D rigid-plastic/viscoplastic mechanics. Different from the conventional rigid-plastic FEM, the velocity field is constructed by the moving least-squares (MLS) approximation. Special emphasis is placed on the treatments of essential boundary conditions, incompressibility constraint and friction boundaries. The stiffness equation for the analysis of 3D bulk metal forming using EFGM is derived and its key algorithms are given. To test the validity of the proposed meshless approach, a typical 3D upsetting forming process is analyzed and the numerical results are compared with those obtained by commercialized rigid-plastic FEM software Deform3D. As results show, when handling 3D plastic deformations, the proposed approach eliminates the need of expensive meshing and remeshing procedures unavoidable in conventional FEM, and still provides results that are in good agreement with finite element predictions. [ABSTRACT FROM AUTHOR]

Objective. To investigate the correlation between the parameters of multi-channel electrogastrography (MEGG) and gastric emptying in patients with functional dyspepsia. Material and methods. The MEGG study included 19 patients with functional dyspepsia and 19 healthy subjects. MEGG was recorded for 30&ThickSpace;min in the fasting state and 60&ThickSpace;min after a standard test meal (450&ThickSpace;kcal). MEGG parameters included the power ratio (PR), the normal percentage of 2–4&ThickSpace;cpm gastric slow waves (N%) and the percentage of slow wave coupling (%SWC). Gastric emptying was measured in the 19 patients by SPECT (single photon emission computerized tomography) and the gastric emptying parameters included lag phase (LP), half time of gastric emptying (T1/2), emptying rate of stable phase (ERSP), one hour retention rate (1HRR), and two hour retention rate (2HRR). Results. No significant difference in MEGG parameters was found between normal subjects and patients. There was a significant negative correlation between postprandial N% and LP ( r = - 0.52, p 1 group, patients in the PR ≤ 1 group had significantly higher T1/2 and 2HRR but lower ERSP. Conclusions. Both the temporal regularity and spatial regularity of gastric slow waves have negative correlations with gastric emptying, which suggests that the impaired gastric myoelectrical activity may be responsible for the delayed gastric emptying in patients with functional dyspepsia. [ABSTRACT FROM AUTHOR]

A systematic machining theory and precision method to determine cutter location in a grinding system is presented for rotary burr. First, the helical cutting edge on various kinds of revolving surfaces is built. Then, based on the geometry model of the helical cutting edge, the smooth spiral rake surface with constant normal rake angle and flank surface can been formed during the one-pass grinding process by this method. No interference between the grinding wheel and workpiece happens by the wheel special rotation. The method has the characteristic of detaching the grinding wheel path solution from specified machining conditions. The grinding wheel path is suitable for different NC machine tools through post processing. Meanwhile, a mechanism kinematic model of the NC machine tool is built, and a generalized algorithm for post-processing of multi-axis NC machine tools is presented. This model is applied to arbitrary configuration of NC machine tool, and the motion value for each axis will be generated by the inputting structure and motion parameters of the machine tool. The model, together with the machining method mentioned in this paper, make the calculation and generation of the grinding wheel path simpler and universal. At last, the validity of the method given in the paper is identified by an example of grinding. [ABSTRACT FROM AUTHOR]

A method to find the principal point of an image plane is proposed in this paper for the case of a pincushion distortion. The analytical foundation of the method is that a pincushion distortion causes a pair of distortion-free parallel lines to become a pair of curves, which are termed conjugate curves in this paper, and the shortest line segment connecting the pair of conjugate curves passes through the principal point. Thus, the principal point can be obtained by computing the intersection point of the shortest line segments of different pairs of conjugate curves. However, the case for a digital image is a bit different from the above. For the same pair of conjugate curves, there is a group of shortest line segments, which is called a shortest segment set. The coincidence region of the shortest segment sets of different pairs of conjugate curves is a polygon, the centroid of which is considered as the principal point. Therefore, the proposed method firstly needs to capture the pincushion-distorted images of some pairs of parallel lines, secondly to find the corresponding polygon and lastly, to calculate the centroid point. A synthetic image and a real image are tested using this method, and the results are satisfying. [ABSTRACT FROM AUTHOR]

The increasingly serious environmental pollution and the shortage of social energy have promoted the rapid development of fuel cell vehicles. The major factor which limits the commercialization of fuel cell vehicles is durability. Accurately estimating the state and parameters of a fuel cell is critical to extending the life of the fuel cell. To address this challenge, we extended a proton exchange membrane fuel cell (PEMFC) lumped parameter model and incorporated new algorithms that are essential to estimate the health of the fuel cell in a range-extended fuel cell car. The unscented Kalman filter (UKF) algorithm has been used to estimate the ohmic internal resistance of the fuel cell in real time. By using the unscented transformation (UT) method, the linearization of the nonlinear state equation is avoided, and the filtering accuracy is improved without increasing the complexity of the system. By comparing simulation and experimental results, the feasibility and accuracy of the algorithm in this paper are further verified. This method has high estimation accuracy and is suitable for an embedded system. The research of this method is an important basis for improving the control strategy of fuel cell vehicles. Reasonable use of fuel cells can extend battery life, and this method is of great significance to the commercialization of fuel cell vehicles. [ABSTRACT FROM AUTHOR]