Optimal design for a VLCC propulsion system based on torsional vibration analysis

AbstractFor main engine changes, shafting torsional vibration of an exported VLCC tanker must be analyzed carefully. With the transition matrix method, the vibration models for the vessel with two different propulsion systems are made. The calculated results show there are forbidden rotated zones which are near to the vessel sailing speed, some necessary measures must be taken to make the forbidden rotated zones change in order that the vessel shafting system is to run safely in the long term instead of main engine changes

Learnable Blur Kernel for Single-Image Defocus Deblurring in the Wild

Recent research showed that the dual-pixel sensor has made great progress in defocus map estimation and image defocus deblurring. However, extracting real-time dual-pixel views is troublesome and complex in algorithm deployment. Moreover, the deblurred image generated by the defocus deblurring network lacks high-frequency details, which is unsatisfactory in human perception. To overcome this issue, we propose a novel defocus deblurring method that uses the guidance of the defocus map to implement image deblurring. The proposed method consists of a learnable blur kernel to estimate the defocus map, which is an unsupervised method, and a single-image defocus deblurring generative adversarial network (DefocusGAN) for the first time. The proposed network can learn the deblurring of different regions and recover realistic details. We propose a defocus adversarial loss to guide this training process. Competitive experimental results confirm that with a learnable blur kernel, the generated defocus map can achieve results comparable to supervised methods. In the single-image defocus deblurring task, the proposed method achieves state-of-the-art results, especially significant improvements in perceptual quality, where PSNR reaches 25.56 dB and LPIPS reaches 0.111.Comment: 9 pages, 7 figure

Essential Role of MFG-E8 for Phagocytic Properties of Microglial Cells

Milk fat globule factor-E8 (MFG-E8) has been regarded as a key factor involved in the phagocytosis of apoptotic cells. We induced a lentivirus into the microglial cells for the augmentation or abrogation of MFG-E8 expression in mouse microglial cells, and investigated phagocytosis of phosphatidylserine tagged human red blood cells (hRBCs) in co-cultures. Increased MFG-E8 levels were associated with a significant increase in phagocytic activity compared to the controls. Conversely, phagocytosis dramitically decreased due to the abrogation of MFG-E8. In addition, the expression of the inflammatory cytokines, TNF-α and IL-1β, also increased or decreased in the microglial cells with the augmentation or abrogation of MFG-E8, respectively. Our findings indicate that the enhanced expression of MFG-E8 could increase phagocytosis of apoptotic cells; conversely, the rate of phagocytosis and the expression of inflammatory cytokines decreased when MFG-E8 expression was knocked down. Our results confirm that MFG-E8 plays an important role in phagocytosis, and possibly serves as an essential signal molecule for microglial cells

Spatiotemporal dynamic evolution and influencing factors of family farms in urban agglomerations in the middle reaches of the Yangtze River

Family farms, considered the most desirable form of Chinese agriculture, play a pivotal role in promoting rural revitalization and agricultural modernization. The purpose of this study was to summarize the spatiotemporal evolution characteristics and influencing factors of family farms to better promote the development of modern agriculture. Using provincial demonstration family farms in the urban agglomeration in the middle reaches of the Yangtze River (MYR-UA) as the research object, this study applied the nearest neighbor index, kernel density analysis, multiscale spatial clustering analysis (Ripley’s K-function), and geographically weighted regression (GWR) model to reveal the spatiotemporal dynamic evolution and influencing factors of family farms. The results indicate that: 1) from 2013 to 2021, family farms exhibited annual increases, and their development stages could be divided into rapid, stable, and slow growth periods. 2) The spatial agglomeration pattern of family farms was significant, and the intercepted points at different time periods show the distribution characteristics of the entire dispersion and local concentration. The spatial evolution characteristics of different types of family farms are nearly consistent with those of the overall family farms. 3) The overall family farms and various types of family farms show a scale effect, which first strengthens and then weakens with the change in geographical distance. 4) The spatial pattern of family farms in MYR-UA is affected by both natural and social factors, of which, social factors had the greatest influence. Finally, based on the findings of the study, policy recommendations for promoting the high-quality development of family farms are proposed

Correlation of Cytokine Levels and Microglial Cell Infiltration during Retinal Degeneration in RCS Rats

Microglial cells, which are immunocompetent cells, are involved in all diseases of the central nervous system. During their activation in various diseases, a variety of soluble factors are released. In the present study, the correlation between cytokine levels and microglial cell migration in the course of retinal degeneration of Royal College of Surgeons (RCS) rats was evaluated. MFG-E8 and CD11b were used to confirm the microglial cells. In the retina of RCS rats, the mRNA expression of seven genes (MFG-E8 and its integrins αυ and ß5, CD11b and the cytokines TNF-α, IL-1ß, and MCP-1) formed almost similar bimodal peak distributions, which were centred at P7 and P45 to P60. In contrast, in rdy rats, which comprised the control group, a unimodal peak distribution centred at P14 was observed. The gene expression accompanied the activation and migration of microglial cells from the inner to the outer layer of the retina during the process of degeneration. Principal component analysis and discriminant function analysis revealed that the expression of these seven genes, especially TNF-α and CD11b, positively correlated with retinal degeneration and microglial activity during retinal degeneration in RCS rats, but not in the control rats. Furthermore, linear regression analysis demonstrated a significant correlation between the expression of these genes and the activation of microglial cells in the dystrophic retina. Our findings suggest that the suppression of microglial cells and the blockade of their cytotoxic effects may constitute a novel therapeutic strategy for treating photoreceptor death in various retinal disorders

Methyl 6-chloro­nicotinate

The mol­ecule of the title compound, C7H6ClNO2, is almost planar, with a dihedral angle of 3.34 (14)° between the COOMe group and the aromatic ring. In the crystal, the mol­ecules are arranged into (12) layers by C—H⋯N hydrogen bonds and there are π–π stacking inter­actions between the aromatic rings in adjacent layers [centroid–centroid distance 3.8721 (4) Å

Modelos lineales generalizados bayesianos para la estandardización de CPUE: aplicación a la pesquería de calamar mediante jigging en el Pacífico noroccidental

Generalized linear Bayesian (GLBM) non-hierarchical and hierarchical models were developed for standardization of catch per unit effort (CPUE). The GLBM containing the covariates of month, latitude, sea surface temperature (SST), sea surface salinity (SSS) and sea level height (SLH) had the best fit for the Chinese squid-jigging fishery of Ommastrephes bartramii in the northwest Pacific Ocean based on deviance information criteria. This best-fitting model tends to be more ecologically sound than other CPUE standardization models, such as generalized linear models and generalized additive models. GLBM was also used to deal with the problems of estimating stock abundance index (i.e. standardized CPUE) resulting from increased spatial heterogeneity of spatial dynamics of fishing efforts in the squid fishery by predicting the standardized CPUE for unfished areas. The standardized CPUE based on data including predicted CPUE of unfished areas was lower than the derived CPUE based on data with observed CPUE alone, in particular during the fishing peak of August to October. This study indicates that it is more appropriate to use the standardized CPUE derived from data including both predicted CPUE of unfished areas and observed CPUE of fished area as a stock abundance index. We suggest that the proposed method be used in CPUE standardization to account for impacts of large spatial heterogeneity of fishing efforts in fisheries.Se desarrollan modelos lineales generalizados bayesianos (GLBM) jerárquicos y no-jerárquicos para la estandardización de captura por unidad de esfuerzo (CPUE). El modelo GLBM seleccionado para la pesquería del calamar Ommastrephes bartramii mediante jigging en el Pacífico noroccidental incorporó las variables explicativas mes, latitud, temperatura superficial del mar (SST), salinidad superficial del mar (SSS) y altura del nivel del mar (SLH). La selección del modelo se basó en el Criterio de Información de la Desviación (DIC). El modelo que mejor se ajustó a los datos tiene más sentido ecológico comparado con modelos de estandardización de CPUE basado en modelos lineales generalizados y modelos aditivos generalizados. Se utilizó también el GLBM para tratar el problema de la estimación de un índice de abundancia del stock (es decir, CPUE estandardizada) frente a la elevada heterogeneidad espacial en la dinámica del esfuerzo en la pesquería del calamar mediante la predicción de la CPUE estandardizada en áreas no pescadas. La CPUE estandardizada en base a los datos que incluyen la CPUE predicha en áreas no pescadas fue inferior a la CPUE derivada en base solamente a la CPUE observada, especialmente durante el pico de pesca de Agosto a Octubre. Este estudio muestra que es más apropiado usar la CPUE estandardizada derivada de datos que incluyen al mismo tiempo la CPUE predicha de las áreas no pescadas y la CPUE observada en el área pescada como índice de abundancia del stock. Se sugiere que se use el método propuesto para la estandardización de CPUE teniendo en cuenta la gran heterogeneidad espacial del esfuerzo pesquero

Dietary Lipoic Acid Influences Antioxidant Capability and Oxidative Status of Broilers

The effects of lipoic acid (LA) on the antioxidant status of broilers were investigated. Birds (1 day old) were randomly assigned to four groups and fed corn-soybean diets supplemented with 0, 100, 200, 300 mg/kg LA, respectively. The feeding program included a starter diet from 1 to 21 days of age and a grower diet from 22 to 42 days of age. Serum, liver and muscle samples were collected at 42 days of age. For antioxidant enzymes, superoxide dismutase (SOD) and glutathione peroxidase (GSH-Px) activity in serum, liver and breast muscle significantly increased in chickens fed with LA. The concentration of malondiadehyde (MDA), an indicator of lipid peroxidation, was significantly lower in serum, liver and leg muscle in birds that received LA than in the control group. Treatments with LA significantly increased glutathione (GSH) content in liver and increased α-tocopherol content in leg muscle as compared to the control. These results indicate that dietary supplementation with 300 mg/kg LA may enhance antioxidant capability and depress oxidative stress in broilers