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The additive manufacturing of directionally solidified Ni-based superalloys remains a significant challenge due to the formation of stray equiaxed grains and their high susceptibility to cracking, particularly for high-volume γ´-type Ni-based superalloys. In this study, a novel strategy based on temperature field management was proposed to prevent hot cracking and control crystallographic texture during laser powder bed fusion (LPBF) of IN738LC superalloy. The influence of laser parameters and substrate preheating on crack density, melt pool morphology, and texture of IN738LC superalloy was investigated. The fluid dynamics and thermal behavior of melt pool was simulated using the discrete element model (DEM) and volume of fluid (VOF) method. The processing window for achieving defect-free IN738LC samples was established and was found to be highly affected by substrate preheating. Substrate preheating at 350 °C resulted in expanded processing window, with the volume energy density ranging from 42.9 to 62.5 J/mm³ without substrate preheating to 40–75 J/mm³. The enlarged processing window was achieved by reducing cracking susceptibility due to the reduced temperature gradient and cooling rate. A unique crystallographic lamellar microstructure (CLM), comprising a -oriented major layer and -oriented sub-layer along the building direction, was successfully achieved in the LPBF-processed IN738LC superalloy. The solidification conditions for obtaining such a CLM were discussed on the aspects of temperature gradient and solidification rate within the melt pool. This work provides new insights and methods for preparing crack-free γ´-Ni-based superalloys with specific textures, which is favorable for improving the high-temperature properties.

Surgical stress is one of the key factors that promote tumor metastasis and recurrence. Adopting corresponding treatment strategies based on the mechanism of surgical stress promoting tumor metastasis and recurrence is of great significance for improving the postoperative prognosis of tumor patients. This article summarized the mechanisms that may affect surgical stress-induced tumor metastasis and recurrences, such as shedding and colonization of circulating tumor cells, changes in postoperative immune microenvironment and postoperative endocrine hormone levels. It also outlined the treatment strategies related to postoperative hormone levels and cytokine regulation, immunotherapy, and tumor vaccines to provide references for the treatment of tumor metastasis and recurrence after surgery.

BackgroundThe floating nuclear power plant (FNPP) is a vital energy supply method for future ocean exploitation and island construction. The typical fuel type of FNPP is similar to the onshore nuclear power plant, i.e., the rod bundle fuel assembly. Due to the effect of ocean waves and wind, the FNNP would be in continuous motion. Rolling is one of the most common types of motion. It can induce the periodical change of the inertial force field of the coolant and the change of flow and heat transfer characteristics of the rod bundle channel. Coupling with neutronic and thermohydraulic, as a result, the operation characteristics, safety, and economics of the FNPP can be affected.PurposeThis study aims to investigate the impact of neutronic-thermo-hydraulic coupling on natural circulation characteristics with the rod bundle channel under rolling motion condition.MethodsA natural circulation system with a 5×5 square array basic rod bundles channel was taken as research object, and it was designed and built on a mechanical rolling platform. Then, based on the point reactor kinetic model, the coupling of neutronic-thermohydraulic-motion was achieved by real-time data acquisition of thermal parameters and calculation of real-time nuclear power, and the effects of fuel temperature feedback and coolant temperature feedback on single-phase natural circulation were considered. Finally, an experimental study on the low-pressure single-phase natural circulation under rolling motion condition was carried out.ResultsUnder static conditions, neutronic-thermo-hydraulic coupling makes the power fluctuate slightly, reactivity and power fluctuation amplitude increase with the increase of temperature feedback coefficient. When the feedback coefficient is lower than -5×10-4 ℃-1, fuel temperature feedback has a greater impact on power than coolant temperature feedback. Increasing the fuel temperature feedback coefficient reduces system stability. Under rolling motion conditions, the smaller the rolling amplitude or the shorter the rolling period, the smaller the amplitude of the introduced power fluctuations. During the initiation of the rolling motion, neutronic-thermo-hydraulic coupling significantly increases 50% of the time for the system to establish a new stable circulation.ConclusionsThese results provide a valuable application for further investigations of the FNNP's design and validation.

BACKGROUND With the increasing concern for food safety, especially for the elemental composition and efficacy of plant-derived foods and health products, research on the nutrient analysis of related foods is continuously carried out. At present, due to the wide variety of agricultural and health products, and the different environments in which the plant matrix grows, the elements absorbed by plants during the growth process vary greatly, making it difficult for many foods to meet the requirements of the calibration and testing system simply by using pure standards. It is necessary to combine the matrix reference materials for calibration and develop new plant-based reference materials. OBJECTIVES To improve the situation that there are few existing plant matrix reference materials, by developing 9 kinds of plant matrix reference materials for elemental analysis. Except for the reference materials for elemental analysis in notoginseng powder, all of them were developed for the first time, which supplemented the types of plant matrix elemental analysis reference materials and were mainly used in food nutrition and safety analysis and testing technology research of plant samples. METHODS In the early stage of development, the selection of candidate reference materials with the representative matrix were investigated and studied. The samples were pretreated, dried, crushed, sieved, and examined by a laser particle size analyzer before being packed in 45mL HDPE plastic bottles and inactivated by 60Co irradiation, which can be stored for a certain period of time. The samples were randomly selected from 30 bottles during the whole packing process, and the homogeneity test was performed by inductively coupled plasma-mass spectrometry (ICP-MS), inductively coupled plasma-optical emission spectrometry (ICP-OES), atomic fluorescence spectrometry (AFS) and volumetric method (VOL). The long-term stability of the reference materials under the specified storage conditions and the transport stability at 60℃ were investigated and the results were evaluated by trend analysis, which showed that the samples were stable under the specified conditions. The operation guideline of reference materials characterization analysis was developed, and 11 laboratories worked together to analyze 59 elements: Ag, Al, As, B, Ba, Be, Bi, Br, Ca, Cd, Ce, Cl, Co, Cr, Cs, Cu, Dy, Er, Eu, F, Fe, Gd, Ge, Hg, Ho, I, K, La, Li, Lu, Mg, Mn, Mo, N, Na, Nd, Ni, P, Pb, Pr, Rb, S, Sb, Sc, Se, Si, Sm, Sn, Sr, Tb, Th, Ti, Tl, Tm, U, V, Y, Yb, Zn. RESULTS The data of the developed series of reference materials were statistically judged by Grubbs and Dixon and the suspicious values were rejected, with a rejection rate of less than 3%. Shapiro-Wilk was used to test the normality of the fixed value data, in which the element Ti in red bean, Bi, I and Th in needle mushroom, Ti in tremella, and I in jasmine had a skewed distribution of the original measurement data, and no certified value was taken only as the median value for reference, and the arithmetic mean of the customized data was used as the certified value for the remaining elements. The certified values and uncertainties of the nine reference materials were above 40, among which, 53 certified values and uncertainties were given for hawthorn and notoginseng. The uncertainty of reference materials consists of homogeneity uncertainty, stability uncertainty and characterization uncertainty. This series of reference materials was developed under the concept of metrological traceability, and a variety of quality control measures were taken to ensure the accuracy and reliability of analytical results and was applied as national level reference materials in 2021. The names and number are as follows: chemical composition of red bean (GBW10228), onion (GBW10232), rape (GBW10233), needle mushroom (GBW10247), tremella (GBW10248), root starch (GBW10249), hawthorn (GBW10250), notoginseng (GBW10251), and jasmine (GBW10234).The existing plant matrix elemental analysis reference materials are mostly found in rice, wheat, tea and other major agricultural and sideline food, and the certified value elements are mainly macronutrients and heavy metals. The present series of reference materials cover agricultural and health products with a large amount of daily sampling, except for notoginseng, which is developed for the first time, supplementing the variety of relevant quality control samples in the food testing field, with 59 certified value elements, which can effectively reflect the composition of elements in relevant products.In this study, more regionally representative candidates were selected, focusing on the beneficial nutritional elements K, Ca, Na, Mg, P, Zn, Fe and harmful metal elements As, Hg, Cd, Pb, whose contents can reflect the distribution characteristics of the elements in different samples and origins, such as red beans, which is a health food, and the candidates were picked from Yi'an County in Songnen Plain (one of the important commodity grain bases in China). It contains high contents of beneficial nutrients such as K (1.392g/100g), Ca (0.104g/100g), Mg (0.165g/100g), P (0.457g/100g), Zn (24μg/g) and Fe (71μg/g), and low contents of Pb (0.033μg/g), Cd (5.4ng/g) and other harmful metal elements, which are far below the national limit standards, reflecting the fertile black soil of Songnen Plain and the effectiveness of China's land management. For elements of Cd and Pb, red beans (5.4ng/g) and (0.033μg/g), onions (17ng/g) and (0.322μg/g), needle mushroom (33ng/g) and (0.126μg/g), rape (170ng/g) and (0.9μg/g), notoginseng (311ng/g) and (0.7μg/g), jasmine (420ng/g) and (1.65μg/g) form a gradient range, which is more applicable for food testing quality control. It can be found that the content of heavy metals in health products such as notoginseng and jasmine are higher than that in vegetable products such as rape and needle mushroom, which has a certain guidance for selecting suitable quality control samples in analytical testing. This is a guideline for the selection of suitable quality control samples.Due to the progress of the current testing methods and instruments, the precision of the data for the determination of rare earths and other elements with very low contents in some samples was good, and standard values were given, such as Eu (9.4±1.7ng/g), Ge (7.8±2.3ng/g), Lu (1.7±0.5ng/g), Tb (5.3±0.9ng/g), Tm (1.8±0.6ng/g) in rape, while the previous reference materials of similar vegetable matrixes did not reach such definite levels. CONCLUSIONS The development of the series of plant matrix reference materials is supplemental and improves the existing plant matrix reference materials, with obvious distribution characteristics of elements and wide applicability of the gradient range. This series of reference substances covers lots of elements with certified values, which is suitable for the quantity transfer and quality control of biological samples analysis and provides basis for the research on the correlation between the medicinal value and elements of health products.

The project aims to investigate the correlation between obesity, overweight, or low body weight and the risk of mortality in sepsis patients. We performed a rigorous and thorough search of major electronic databases, including PubMed, Web of Science, EMBASE, and Cochrane Library, from the inception of these databases up to March 28, 2023. The data were analyzed with Stata software (version 16.0). Twelve studies incorporating 521,207 individuals were enrolled. The results demonstrated that obesity (OR = 0.82; 95% CI: 0.69–0.97; P

Abstract Krabbe disease (KD) and metachromatic leukodystrophy (MLD) are caused by accumulation of the glycolipids galactosylceramide (GalCer) and sulfatide and their toxic metabolites psychosine and lysosulfatide, respectively. We discovered a potent and selective small molecule inhibitor (S202) of ceramide galactosyltransferase (CGT), the key enzyme for GalCer biosynthesis, and characterized its use as substrate reduction therapy (SRT). Treating a KD mouse model with S202 dose-dependently reduced GalCer and psychosine in the central (CNS) and peripheral (PNS) nervous systems and significantly increased lifespan. Similarly, treating an MLD mouse model decreased sulfatides and lysosulfatide levels. Interestingly, lower doses of S202 partially inhibited CGT and selectively reduced synthesis of non-hydroxylated forms of GalCer and sulfatide, which appear to be the primary source of psychosine and lysosulfatide. Higher doses of S202 more completely inhibited CGT and reduced the levels of both non-hydroxylated and hydroxylated forms of GalCer and sulfatide. Despite the significant benefits observed in murine models of KD and MLD, chronic CGT inhibition negatively impacted both the CNS and PNS of wild-type mice. Therefore, further studies are necessary to elucidate the full therapeutic potential of CGT inhibition.

In view of the deformation and instability law of hard roof without side filling retaining roadway, based on the systematic construction and analysis of the force and bearing model of roadway retaining structure, this article proposes the control mechanical model and calculation method of roadway retaining, which takes the anchor roof beam and the key block above to form the cantilever beam together, with the anchor solid coal side as the foundation support. The research and practice show that under the condition of hard roof, the mechanical connection between the roof of gob-side entry retaining and the roof of mining face can be effectively cut off so as to improve the structural configuration and mechanical properties of the lateral roof of gob-side entry retaining and the key blocks above, and reduce the damage of upper strata subsidence and goaf roof collapse to the roof of roadway. Then, through strengthening by anchor to significantly enhance solid coal side, bearing capacity of anchor roof beam, so they can share the upper strata caused by the load and deflection of mining influence, in addition, the roof bolting, reinforcement of waste rock bolting supporting role can better improve the structure for stability, adaptability and engineering applicability, this method is successfully applied in engineering practice. It is worthy of further research and application.

The fundamental characteristics of agricultural products are appearance, size, and weight, which affect their market value, consumer preference, and choice. Thus, food and agricultural industries seek rapid, simple, and nondestructive approaches to assess real-time measurements at the post-harvest stage before packaging for the consumer market. While sorting and grading may be performed by humans, it is unreliable, time-consuming, complicated, subjective, onerous, expensive, and easily influenced by surroundings. Therefore, an astute sorting and grading method for tomato fruit is required. We evaluated two tomato configurations on a conveyor belt: single tomatoes (no occlusion) and multi-tomatoes (partially occluded). We used polygon approximation for concave and convex point extraction algorithms to segment the occluded tomatoes. We developed seven models for regression using single-tomato image features. The Bayesian regularization artificial neural network outranked all the trained models in weight estimation with a root-mean-square error (RMSE) of 1.468 g and R2 of 0.971. For volume estimation, the RBF SVM had the best performance with R2 of 0.982 and RMSE of 1.2683 cm3. It is feasible to implement a proposed system as a noninvasive in-line sorting technique for tomatoes.

The efficiency of the fabrication and the cost of feedstock materials are important constraining factors for a wider application of the laser powder bed fusion (LPBF) process in the industry. Therefore, it is necessary to investigate the feasibility of using different particle size distributions (PSD) combined with higher layer thickness for achieving higher building efficiency and cost-effectiveness. This paper focuses on the effect of PSD (0–53, 15–53, 15–75, and 15–105 μm) on the print quality and mechanical properties of the LPBF-processed Ti-6Al-4V at a layer thickness of 60 μm. The results show that volumetric energy density (VED) range, which allows the coarse powder to reach full density, becomes relatively narrower but is still capable of producing fully dense parts when the parameters are properly adjusted. Among the fully dense specimens, the surface roughness varies slightly with the increase of VED and PSD. In the case of proper parameter selection, specimens made of coarse powder can still achieve low surface roughness. Only slight differences in mechanical performance are found for specimens produced using different PSD powders as they have almost identical microstructures. The issue of the anisotropic mechanical properties of the as-built specimens is resolved after annealing treatment at 800 °C for 2 h. This study provides a guideline for producing high-quality Ti-6Al-4V parts using a higher layer thickness and coarser powders.

ABSTRACT: In a broiler carcass production conveyor system, inspection, monitoring, and grading carcass and cuts based on computer vision techniques are challenging due to cuts segmentation and ambient light conditions issues. This study presents a depth image-based broiler carcass weight prediction system. An Active Shape Model was developed to segment the carcass into 4 cuts (drumsticks, breasts, wings, and head and neck). Five regression models were developed based on the image features for each weight estimation (carcass and its cuts). The Bayesian-ANN model outperformed all other regression models at 0.9981 R2 and 0.9847 R2 in the whole carcass and head and neck weight estimation. The RBF-SVR model surpassed all the other drumstick, breast, and wings weight prediction models at 0.9129 R2, 0.9352 R2, and 0.9896 R2, respectively. This proposed technique can be applied as a nondestructive, nonintrusive, and accurate on-line broiler carcass production system in the automation of chicken carcass and cuts weight estimation.

The appearance, size, and weight of poultry meat and eggs are essential for production economics and vital in the poultry sector. These external characteristics influence their market price and consumers' preference and choice. With technological developments, there is an increase in the application and importance of vision systems in the agricultural sector. Computer vision has become a promising tool in the real-time automation of poultry weighing and processing systems. Owing to its noninvasive and nonintrusive nature and its capacity to present a wide range of information, computer vision systems can be applied in the size, mass, volume determination, and sorting and grading of poultry products. This review article gives a detailed summary of the current advances in measuring poultry products' external characteristics based on computer vision systems. An overview of computer vision systems is discussed and summarized. A comprehensive presentation of the application of computer vision-based systems for assessing poultry meat and eggs was provided, that is, weight and volume estimation, sorting, and classification. Finally, the challenges and potential future trends in size, weight, and volume estimation of poultry products are reported.