Distribution In Different Regions Research Articles

The effect of hyperlipidemia and body fat distribution on subclinical left ventricular function in obesity: a cardiovascular magnetic resonance study

BackgroundObesity is often associated with multiple comorbidities. However, whether obese subjects with hyperlipidemia in the absence of other complications have worse cardiac indices than metabolically healthy obese subjects is unclear. Therefore, we aimed to determine the effect of hyperlipidemia on subclinical left ventricular (LV) function in obesity and to evaluate the association of cardiac parameters with body fat distribution.Materials and methodsNinety-two adults were recruited and divided into 3 groups: obesity with hyperlipidemia (n = 24, 14 males), obesity without hyperlipidemia (n = 25, 13 males), and c ntrols (n = 43, 25 males). LV strain parameters (peak strain (PS), peak diastolic strain rate (PDSR), peak systolic strain rate) derived from cardiovascular magnetic resonance tissue tracking were measured and compared. Dual-energy X-ray absorptiometer was used to measure body fat distribution. Correlations of hyperlipidemia and body fat distribution with LV strain were assessed by multivariable linear regression.ResultsObese individuals with preserved LV ejection fraction showed lower global LV longitudinal, circumferential, and radial PS and longitudinal and circumferential PDSR than controls (all P < 0.05). Among obese patients, those with hyperlipidemia had lower longitudinal PS and PDSR and circumferential PDSR than those without hyperlipidemia (− 12.8 ± 2.9% vs. − 14.2 ± 2.7%, 0.8 ± 0.1 s−1 vs. 0.9 ± 0.3 s−1, 1.2 ± 0.2 s−1 vs. 1.4 ± 0.2 s−1; all P < 0.05). Multivariable linear regression demonstrated that hyperlipidemia was independently associated with circumferential PDSR (β = − 0.477, P < 0.05) in obesity after controlling for growth differences, other cardiovascular risk factors, and central fat distribution. In addition, android fat had an independently negative relationship with longitudinal and radial PS (β = − 0.486 and β = − 0.408, respectively; all P < 0.05); and visceral fat was negatively associated with longitudinal PDSR (β = − 0.563, P < 0.05). Differently, gynoid fat was positively correlated with circumferential PS and PDSR and radial PDSR (β = 0.490, β = 0.481, and β = 0.413, respectively; all P < 0.05).ConclusionHyperlipidemia is independently associated with subclinical LV diastolic dysfunction in obesity. Central fat distribution (android and visceral fat) has a negative association, while peripheral fat distribution (gynoid fat) has a positive association on subclinical LV function. These results suggest that appropriate management of hyperlipidemia may be beneficial for obese patients, and that the differentiation of fat distribution in different regions may facilitate the precise management of obese patients.Clinical trials registration Effect of lifestyle intervention on metabolism of obese patients based on smart phone software (ChiCTR1900026476).

Modelling and optimization of Li+ extraction from brine with high Mg/Li ratio by electrochemically switched ion exchange considering thermodynamics and dynamics simultaneously

Electrochemically switched ion exchange (ESIX) technology has been proven to be an efficient and environmental-friendly method for extracting Li+ from brine lakes. To deeply understand and mathematically express the underlying physical process of Li+ extraction in ESIX, a model is developed to describe Li+ extraction from brine lakes with a high Mg/Li mass ratio (500:1) by ESIX with an electrode coated with λ-MnO2 film. The kinetics and thermodynamics of the Li+ extraction process is considered simultaneously by coupling the Frumkin-Bulter-Volmer theory modified by electroactive site concentration with a modified Gouy-Chapman-Stern model. The local sensitivity analysis indicates that the performance of ESIX in Li+ adsorption is greatly influenced by cell voltage, film mass, and Stern capacitance of carbon black film, whereas these parameters have little effect on Mg2+ adsorption. The individual parameter analysis elucidates that the mass and Stern capacitance of carbon black film can regulate the potential drop distributions in different regions of ESIX system, resulting in a maximum Li+ extraction efficiency of 90.22 % due to the increased driving force in the faradic reaction and reduced charge transfer resistance. The optimization of combined parameters indicates that the optimum operation can be achieved at the conditions with a cell voltage ranging between 1.0 and 1.2 V, a Stern layer capacitance with electric double layer volume for carbon black film of 5.4 × 107 F/L, and an initial Li+ content of the treatment solution: carbon black film: λ-MnO2 film mass ratio of 0.1 kg: 9 kg: 8 kg.

Seroprevalence of Hepatitis C Virus in the Urban Commune of Kindia-Republic of Guinea

Introduction: Hepatitis C is an inflammation of the liver caused by the hepatitis C virus; its spread in humans has been boosted by the emergence of parenteral use for medical purposes or drug injections, as well as its asymptomatic nature in the acute phase.&#x0D; The global prevalence of hepatitis C is estimated at 1%, with a variable distribution in different regions of the world, sometimes even within the same country.&#x0D; General objective: To help improve the biological diagnosis and prevention of HCV infections in the urban commune of Kindia.&#x0D; Methodology: The urban commune of Kindia was used as the study area. This prospective and descriptive study was carried out at the Institut de Recherche en Biologie Appliquée de Guinée (IRBAG) from June to December 2022. The biomaterial consists of 3,000 blood samples taken from patients attending consultations at health facilities. The Immuno-Enzymatic technique (ELISA) was used to test for anti-HCV antibodies.&#x0D; Results: In the course of our work, out of 3,000 samples taken from patients admitted to health facilities, 78 cases tested positive for the anti-HCV antibody, representing a carriage rate of 2.6%.  Females were the most affected, with 50 positive cases (1.67%). The 31-40 age group had the highest anti-HCV antibody carriage rate, at 0.70%.&#x0D; Conclusion: All socio-professional groups are affected by this infection, but to varying degrees. Despite our efforts, hepatitis C virus infection remains a major concern, as there is currently no vaccine and existing treatments are expensive and inaccessible to middle-income countries.

Application of Gaussian Mixture Models for aerosol type analysis in China

The relative contributions of different aerosol types to the total aerosol content were determined using sun photometer derived inversion data from four Aerosol Robotic Network (AERONET) stations in China, i.e. Beijing, NUIST, Hong Kong PolyU and SACOL. Five main aerosol types were considered: dust (DU), mixed (MI), urban industry (UI), biomass burning (BB) and maritime (MA). The identification of these aerosol types is based on cluster analysis using Gaussian mixture models (GMMs), together with the Mahalanobis distance (MD) to each reference centroid. The results show that the aerosol types are distinctly different between the different sites as regards fine and coarse particles. MI is the dominant aerosol type at four locations, with the largest contribution at NUIST (73.4%). The largest contribution of DU (18.8%) is observed at SACOL and at Beijing the contribution of UI is largest (33.7%). BB contributions are relatively small, with the largest at NUIST (2.7%). For the analysis, two periods are considered, i.e. before and after the implementation of the national ambient air quality standard (GB3095–2012) in 2012. The clustering results revealed a changing trend in the proportion of UI and MI aerosols in Chinese cities. Although the proportion of UI aerosols has increased, MI aerosols still remain dominant. The proportion of DU in SACOL station also increased. The seasonal analysis shows that DU dominates in spring at the SACOL station (55.3%), which is near the dust source area. Among the other stations, the contribution of DU due to long-range transport from the source regions, is largest (10.6%) in Beijing, with a small contribution at NUIST. The aerosol volume size distributions in different regions exhibit substantial differences due to variations in aerosol types: Beijing and SACOL are dominated by coarse mode particles, while NUIST and Hong Kong PolyU are dominated by fine mode particles.

Marine Bacterial Communities in the Xisha Islands, South China Sea

Oligotrophic marine environments are ecological funnels in marine ecosystems and are essential for maintaining the health and balance of the entire marine ecosystem. Bacterial communities are one of the most important biological populations, which can survive in low-nutrient environments and perform a variety of important ecological functions, such as decomposing and absorbing organic waste in the ocean and converting nitrogen from the atmosphere into a usable nitrogen source, thus maintaining the health of marine ecosystems. The bacterioplankton community composition and potential function were analyzed using 16S rRNA gene amplicon sequencing in oligotrophic coral reef sea areas. The diversity of the bacterial community exhibited significant differences between the four studied regions. Proteobacteria (38.58–62.79%) were the most abundant in all sampling sites, followed by Cyanobacteria (15.41–37.28%), Bacteroidota (2.39–6.67%), and Actinobacteriota (0.45–1.83%). Although bacterioplankton communities presented no difference between surface and bottom water regarding community richness and α-diversity, the bacterial community composition presented significant differences between surface and bottom water regarding β-diversity. Alteromonadales, Rhodospirllales, and Chloroplast were identified as the significantly different communities between the surface and bottom (Q value &lt; 0.01). Bacterial community distribution in different regions was mainly affected by pH, dissolved oxygen, and nutrients. Nitrite ammonification, chitinolysis, predatory or exoparasitic, chloroplasts, chemoheterotrophy, aerobic chemoheterotrophy, phototrophic, compound degradation (mostly nutrients and pollutants), nitrogen cycle, fermentation, and intracellular parasitism were the dominant functions in the four regions.

Study on the Spatial Pattern and Influencing Factors of Scenic Villages in Shandong Province

Based on the data of 859 scenic villages in Shandong Province, the spatial pattern of scenic villages in Shandong Province and various prefectural cities and the factors affecting them were quantitatively studied by using spatial analysis methods such as average nearest neighbor index method and kernel density analysis, as well as combining with geodetic detector analysis tools. The results show that: (1) the scenic villages in Shandong Province have significant aggregation distribution characteristics, but there are differences in the spatial types of scenic villages in different prefectural-level cities; (2) the scenic villages in Shandong Province show the spatial distribution characteristics of "three core dense areas and multiple sub-core dense areas", and the spatial distribution in different regions has significant differences. The spatial distribution of scenic villages in Shandong Province is characterized by The "three core intensive areas" are Taian-Jinan, Zibo-Weifang central Luzhong core agglomeration area and Rizhao-Qingdao east Luzhong core intensive area; (3) scenic villages in Shandong Province are affected by a combination of natural conditions, socio-economic conditions, tourism resource conditions, and transportation conditions, among which there is a strong dependence on river density and the number of tourists received.

New findings on choroidal features in healthy people by ultra-widefield swept-source optical coherence tomography angiography

To evaluate the distribution of choroidal thickness (CT) and its trend with age in healthy people using 120° ultra-wide field swept-source optical coherence tomography angiography (UWF SS-OCTA). In this cross-sectional observational study, healthy volunteers underwent single imaging of the fundus with UWF SS-OCTA at a field of view (FOV) of 120° (24 mm × 20 mm) centered on the macula. The characteristics of CT distribution in different regions and its changes with age were analyzed. A total of 128 volunteers with a mean age of 34.9 ± 20.1 years and 210 eyes were enrolled in the study. The thickest mean choroid thickness (MCT) was located at the macular region and supratemporal region, followed by the nasal side of the optic disc, and thinnest below the optic disc. The maximum MCT was: 213.40 ± 36.65 μm for the group aged 20–29, and the minimum MCT was: 162.11 ± 31.96 μm for the group aged ≥ 60. After the age of 50, MCT was significantly and negatively correlated decreased with age (r = − 0.358, p = 0.002), and the MCT in the macular region decreased more remarkably compared to other regions. The 120° UWF SS-OCTA can observe the distribution of choroidal thickness in the range of 24 mm × 20 mm and its variation with age. It was revealed that MCT decreased more rapidly in the macular region relative to other regions after 50 years old.

Analyzing the acoustic wave propagation characteristics in discontinuous bifurcated waveguide

This article examines the dispersion characteristics and energy distribution in different regions of the bifurcated waveguide with vertical step discontinuities. In this research study, we have considered mathematical model of noise reduction devices, specifically analyzing the acoustic wave propagation problem in a bifurcated waveguide with elastic membrane outer plates and rigid inner plates. Mode-matching (MM) technique is employed to match the eigenfunctions at the interface and analyzed the reflection and transmission amplitudes in all regions. Through MM scheme an infinite system of equations has been obtained for these boundary conditions by dividing the structure into three regions and finding dispersion relations and eigenfunctions using separation of variables and the corresponding orthogonality relations. Because of the flexible nature of the boundary surfaces, the acquired eigenfunctions and the dispersion relation do not satisfy the standard orthogonality relation. To resolve this difficulty, we have established a modified orthogonality relation to take into account the flexible nature of the boundary surfaces. With the implication of physical connections, the uniqueness of the problem has been ensured, and zero displacement and zero gradient edge conditions on bending surfaces have been considered to present results. Energy expressions are obtained showing how the energy is distributed in different sections of the waveguide, which is consistent with the energy conservation law. Finally, the numerical discussion illustrates the quantitative behavior of the physical parameters and summarizes the significant contribution of the study by presenting graphical data.

Textural and microstructural analyses and ranking of the process parameters in hydro-mechanical deep drawing of AZ31B magnesium sheets

The present research work is a comprehensive study on the hydro-mechanical deep drawing (HMDD) process of AZ31B magnesium alloy at elevated temperatures. Several process parameters including the forming temperature, fluid pressure and initial blank diameter were considered to conduct a full factorial experiment. The changes in the thickness strain and thickness variation of the final product were also chosen as the responses. The outcomes gained from the design of experiment technique demonstrated that the initial blank diameter (with 31.3%), process temperature (with 30.2%) and the fluid pressure (with 18.4%) were respectively the most important factors affecting the quality and homogeneity of the AZ31B drawn cup. Moreover, the appropriate process temperature and fluid pressure for HMDD operation of this alloy were, in turn, 200 °C and 15 MPa. Afterwards, a complete texture analysis was carried out and its relation with the hardness distribution in different regions of the workpiece was examined. In addition, the correlation between the microstructures, obtained from the optical microscopy, scanning electron microscopy and X-ray diffraction, with findings of the hardness tests was studied for the optimally produced cup. Based on the textural inspections, it was found that reduction in the basal texture of the flange area in comparison with the bottom of the product was about 12.5%. Moreover, the maximum increase in the hardness (about 24%) and decrease in the average grain size (about 42%) occurred in the wall area of the final product.

Epidemiology and etiology of chemical ocular injury: A brief review.

Chemical ocular injury is one of the common ophthalmologic emergencies that can cause vision loss and serious complications. Despite all protective measures, it continues to be a serious public health problem, especially in young male patients. Although it is known that injuries occur most frequently in the workplace and in young male patients, there is a variable frequency and distribution in different regions around the world. In addition, with the coronavirus disease 2019 pandemic, there are changing trends in ocular chemical injuries. This review aims to specify an update on the epidemiological and etiological features of ocular chemical injuries.

Study on Atmospheric Stability and Wake Attenuation Constant of Large Offshore Wind Farm in Yellow Sea

Power generation estimation is one of the key steps in wind farm micro-sitting, and its accuracy is related to the wake decay constant in the wake model. Considering the influence of wind resource distribution in different regions, this study carried out interval optimization for the wake decay constant of offshore wind farms in the Yellow Sea region of China. Given the very small length of the sea surface roughness, atmospheric stability is a critical factor influencing the wake extent and recovery speed of offshore wind farms. WAsP 10 (Wind Atlas Analysis and Application software) simulates the wake of various scenarios, and the selection range of wake attenuation constant is investigated by combining the cases of two offshore wind farms in the Yellow Sea region. The study found that the higher the atmospheric stability, the larger the wake and the lower the wake attenuation coefficient. The Yellow Sea wind farm’s wake error system is between 0.03 and 0.04, and the forecast error can be controlled to within 3%. When simulating the wind farm at Yellow Sea offshore for improving power generation and economic evaluation, it is critical to select the correct value range of wake decay constant.

Implementation of SOLPS-ITER code with new Grad–Zhdanov module for D–T mixture

A new Grad–Zhdanov module is implemented into the SOLPS-ITER code for calculation of the parallel kinetic coefficients. A complete, multi-ion generalization is performed, relaxing the heavy impurity assumption. A JET-like D+T+Ne test simulation is conducted to demonstrate the ability to model a 50/50 deuterium (D) and tritium (T) mixture in SOLPS-ITER. More than 30% T build-up with respect to D is observed in different parts of the simulation domain, in particular at the high field side. A T predominance over D is also observed near both the inner and outer targets. It is a result of the different effective diffusion, dominated by charge-exchange processes, for the D and T neutral species. A simple 1D model is proposed to describe this phenomenon. The contribution to the differing D and T distribution in different regions from the Grad–Zhdanov thermal force is also studied. Due to the thermal force and the D/T poloidal flow from the low field side to the high field side, the prevalence of the T species over D is found at the high field side at the X-point level. The latter leads to an inner–outer divertor asymmetry of . However, the effect is relatively small due to the close D and T masses. It is further shown that the infinite ion mass difference limit, which is used for the derivation of the Zhdanov-Yushmanov analytical expressions and applied for the thermal force coefficient calculation previously used in the SOLPS-ITER code, overestimates significantly. Thus, the old SOLPS-ITER model should not be applied for D–T simulations. Finally, possible experimental studies of the D and T spatial separation due to the new effects revealed by this modelling are discussed.

Visualization and quantification of low-velocity impact damage of three-dimensional braided CFRP composites by micro-computed tomography

In this paper, the low-velocity impact response and damage of three-dimensional five-directional (3D5d) braided carbon/epoxy composites under different energies (30 J, 65 J, 100 J) are studied. Importantly, the damage is segmented from the axial and radial directions of the yarn to visualize and quantify the damage distributions in different regions based on micro-CT. The results show that as compared with the samples under 30 J and 100 J, the samples under 65 J energy perform higher impact properties. Moreover, as the impact energy increases from 30 J to 100 J, the corresponding damage volume increases from 6.886 mm3 to 477.133 mm3. Furthermore, the damage distributions are almost symmetrical in space.

Genetic characterization of two North Italian villages: A story of isolation, ancient admixture, and genetic drift

AbstractObjectivesPopulation isolates represent a focus of interest because of their particular genetic history and the possibility of mapping peculiar deleterious variants. Here we investigated the pattern of genetic variation in two North Italian villages: Rotzo (RTZ) and Stoccareddo (STC), in the Asiago plateau.Materials and methodsWe genotyped over 800 individuals for more than 600.000 markers. We investigated the isolation level by analyzing runs of homozygosity (ROH) and the level of population structure. Then we estimated the time of admixture and the relationship between ancient genomes and these two villages. Finally, we looked at the effect of genetic drift on deleterious variants.ResultsWe highlighted a different isolation level between RTZ and STC; despite the average number of ROH being similar between the two villages, RTZ shows a higher level of total homozygosity. We estimated, from different sources, that the time of admixture for the ancestors of these two populations was between 113 and 88 generations ago.We discovered that a deleterious variant in MCUB gene (rs78025076), which is linked to several lipid traits, is entirely absent in RTZ and at 1%frequency in STC. In contrast, the risk allele frequency is 2% in Europe and 2.4% in North‐East Italy.DiscussionThese results show the importance of a genetic characterization of geographically isolated populations. Their vast array of past history could highlight specific events in the past and help describe deleterious variants and traits distribution in different regions.

Research on the efficiency evaluation of heat pipe PV/T systems and its applicability in different regions of China

As a passive heat transfer system, the heat pipe is becoming an important way to solve the problem of heat loss and heat accumulation in PV/T systems. However, the evaluation of the annual average efficiency of heat pipe PV/T systems in the existing studies does not consider the efficiency under different solar radiation and the difference in the annual solar radiation distribution in different regions. The purpose of this study is to propose a method for the annual average efficiency evaluation of heat pipe PV/T systems (AEHP method), which comprehensively considers the efficiency differences under different radiation and the distribution of solar radiation of different intensities in the typical year. The calculation results are more accurate, which will promote the reasonable evaluation and engineering application of heat pipe PV/T systems. Firstly, the dimensionless models of different radiation and their performance (photovoltaic efficiency, photothermal efficiency, and comprehensive efficiency) are established by experimental tests on the heat pipe PV/T system in this paper. Secondly, the frequencies and frequency of solar radiation in different intervals of the typical year in major cities of China are analyzed statistically, and the radiation frequency method is proposed. Thirdly, the average efficiencies of heat pipe PV/T systems in the existing literature are obtained by statistical analysis. Combined with the radiation frequency method, an annual average efficiency evaluation method of heat pipe PV/T systems (AEHP method) is proposed. The annual average efficiency of heat pipe PV/T systems in different regions is obtained. Finally, the annual heat collection and power generation of heat pipe PV/T systems are calculated based on the AEHP method, and provide a scientific and reasonable evaluation method for the promotion and application of heat pipe PV/T systems.

Biological and Chemical Diversity of Angelica archangelica L.—Case Study of Essential Oil and Its Biological Activity

Garden angelica (Angelica archangelica L.), native to the northern temperate region, is widespread in Europe and Asia. Since the middle ages, it has been used for healing and as a vegetable in traditional dishes. In the modern era, it has been proven that A. archangelica has a complex chemical composition. The main derivatives that contribute to the plant’s biological activities are essential oil and coumarins. In this review, the focus is on the cross-analysis of the taxonomy of A. archangelica, and its distribution in different regions, with the presentation of the richness of its biochemical composition, which overall contributes to the widespread use of the roots of this plant in folk medicine. It belongs to the plants that were introduced to the wider area of Central, Eastern, and Southern Europe; as a medicinal plant, it represents a significant part of the medical flora of many areas. Cluster analysis of pooled data indicates a clear differentiation of chemotypes.

Long-term thermomechanical displacement prediction of energy piles using machine learning techniques

Energy piles have attracted much attention in recent years because they provide a profitable solution for efficient shallow geothermal energy utilization in different climatic regions. However, the long-term performance design of energy piles under different thermal scenarios currently relies on time-consuming and computationally expensive methods such as numerical simulations, which seriously hinders the further engineering application of energy piles. To this end, this paper provides a high-precision and computationally efficient model for predicting the long-term performance of energy pile design through an artificial neural network machine learning process. First, experimentally validated numerical models are developed. Then, they are utilized to generate the training and evaluate datasets for the proposed model by inputting sixty typical thermal load distributions in different regions of China. Finally, the performance of the proposed model is evaluated by comparing its calculations with those obtained using numerical models. The results show that the proposed model can predict the long-term performance of energy piles and enrich the current methods for the long-term design of energy piles. Furthermore, its features that tremendously reduce the computational time and minimum required resources make it an excellent supplement compared with numerical simulations.

Finite Element Analysis and Forming Test of Roll Forging of Thin - wall Inner and Outer Gear Cup

In this paper, a new forming process method for cup-shaped parts with internal and external teeth structure is proposed, and the forming principle is expounded. The forming characteristics of cup-shaped parts with internal and external teeth are analyzed by finite element method. The stress and strain distribution in different regions of internal teeth, external teeth and side wall are studied. The most prone areas of defects are predicted. The process parameters are determined by simulation. The sample trial production is completed on GD 62-380 roll forging machine, and the comprehensive performance test is verified by carrying HPT330 hydraulic automatic gearbox bench.

Microstructure, mechanical properties and fatigue behaviors of linear friction welded weathering steels

The weathering steels SMA490AW and SPA-H with a high phosphorus content were successfully joined by linear friction welding (LFW) without welding defects and heat affected zone (HAZ) softening. The residual stress of the welded joints was measured by X-ray diffraction (XRD) after the welding. The microstructure characteristics were observed using a scanning electron microscope (SEM) and analyzed corresponding to the microhardness distribution in different regions. The mechanical properties and fatigue behaviors were assessed using the digital image correlation (DIC). The results suggest that the bainites were crystallized in the weld center zone (WCZ), and the area fraction of bainites was obviously decreased at a small distance from the WCZ, which illustrated a large welding temperature gradient. The ductile fracture of LFW joints occurred at the base metal part of the specimens, resulting in a joint efficiency close to 100%. The fatigue strength of LFW joints was close to that of base metals and the proposed S-N curves showed a much higher fatigue strength compared to the design curve FAT112.

Development of a lipid metabolism-related gene model to predict prognosis in patients with pancreatic cancer.

BACKGROUNDPancreatic cancer is a highly heterogeneous disease, making prognosis prediction challenging. Altered energy metabolism to satisfy uncontrolled proliferation and metastasis has become one of the most important markers of tumors. However, the specific regulatory mechanism and its effect on prognosis have not been fully elucidated.AIMTo construct a prognostic polygene signature of differentially expressed genes (DEGs) related to lipid metabolism.METHODSFirst, 9 tissue samples from patients with pancreatic cancer were collected and divided into a cancer group and a para-cancer group. All patient samples were subjected to metabolomics analysis based on liquid tandem chromatography quadrupole time of flight mass spectrometry. Then, mRNA expression profiles and corresponding clinical data of pancreatic cancer were downloaded from a public database. Least absolute shrinkage and selection operator Cox regression analysis was used to construct a multigene model for The Cancer Genome Atlas.RESULTSPrincipal component analysis and orthogonal projections to latent structures-discriminant analysis (OPLS-DA) based on lipid metabolomics analysis showed a clear distribution in different regions. A Euclidean distance matrix was used to calculate the quantitative value of differential metabolites. The permutation test of the OPLS-DA model for tumor tissue and paracancerous tissue indicated that the established model was consistent with the actual condition based on sample data. A bar plot showed significantly higher levels of the lipid metabolites phosphatidylcholine (PC), phosphatidyl ethanolamine (PE), phosphatidylethanol(PEtOH), phosphatidylmethanol (PMeOH), phosphatidylserine (PS) and diacylglyceryl trimethylhomoserine (DGTS) in tumor tissues than in paracancerous tissues. According to bubble plots, PC, PE, PEtOH, PMeOH, PS and DGTS were significantly higher in tumor tissues than in paracancerous tissues. In total, 12.3% (25/197) of genes related to lipid metabolism were differentially expressed between tumor tissues and adjacent paracancerous tissues. Six DEGs correlated with overall survival in univariate Cox regression analysis (P < 0.05), and a 4-gene signature model was developed to divide patients into two risk groups, with patients in the high-risk group having significantly lower overall survival than those in the low-risk group (P < 0.05). ROC curve analysis confirmed the predictive power of the model.CONCLUSIONThis novel model comprising 4 lipid metabolism-related genes might assist clinicians in the prognostic evaluation of patients with pancreatic cancer.