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Additive manufacturing (3D printing) technologies, especially vat photopolymerization (VPP), provide a cost-effective and efficient approach for the fabrication of heat dissipation devices with complex geometric designs. The incorporation of inorganic thermal conductive fillers into resin matrix is widely recognized as an effective way to enhance thermal conductivity. Notably, the synergistic effect of hybrid fillers can further enhance thermal conductivity. However, the consequent drastic increase in viscosity of the UV-curable resin may decrease the success rate and accuracy of printing on commercial VPP 3D printers. In this work, hexagonal boron nitride (h-BN) platelets and spherical h-BN together with β-Si 3 N 4 are introduced into the UV-curable resin system. Corresponding results proved that h-BN together with β-Si 3 N 4 provide a synergistic effect on the thermal conductivity enhancement compared to the filler in single morphology only. Moreover, owing to the spherical structure, low-viscosity UV-curable resin with high solid content can be prepared. In specific, a thermal conductive polymer composite material with a solid content of 60 wt% is prepared, which exhibits high thermal conductivity (1.42 W/mK), representing an enhancement of up to 610 % compared to neat resin. In subsequent application demonstrations, 3D printed heat dissipation devices with as-prepared resin composite material have been shown to effectively enhance the heat dissipation rate for the heating device. [ABSTRACT FROM AUTHOR]

[Display omitted] • 25-Hydroxyvitamin D 3 usage in nursery pigs has a compensatory effect on growing pigs. • 25-Hydroxyvitamin D 3 improves growth and bone performance in finishing pigs. • 25-Hydroxyvitamin D 3 enhances the deposition of polyunsaturated fatty acids in pork. • 25-Hydroxyvitamin D 3 increases the body's calcium absorption and antioxidant level. The study was conducted to evaluate effects of short-term or long-term administration of 25- hydroxyvitamin D 3 [25(OH)VD 3 ] on growth performance, bone characteristics, meat quality in growing pigs. A total of 144 pigs were allocated into three groups and fed diet contained 2000 IU vitamin D 3 (VD 3) or 25(OH)VD 3 for a short-term and long-term administration. The results showed that long-term 25(OH)VD 3 administration increased BW on d 56 and average daily gain in d 28–56. Furthermore, long-term feeding increased bone calcium content and mRNA expressions of calcium ion channel protein and anti-oxidases genes in the liver. In short, adding 25(OH)VD 3 to the diet improved weight gain, bone characteristics, deposition of polyunsaturated fatty acids and antioxidant capacity compared with the VD 3 , while the long-term feeding of 25(OH)VD 3 was particularly effective focusing on calcium deposition and mRNA expression of GPx1, Cu/Zn SOD and CaBP-D9K. [ABSTRACT FROM AUTHOR]

Energy saving and emission reduction in traditional manufacturing can be achieved by reducing the occurrence of defective products. Most of the existing optimization methods are obtained by referring to production experience and technical manual, which are time-consuming and laborious. Thus, a method of process selection and optimization for defective products in the design phase is required. In this paper, a process design strategy based on design parameters for eliminating sand casting defects is proposed. Firstly, the technological process and hole-type defects of sand casting are analyzed. The process design parameters are divided into three categories to propose a process design strategy. Three specific optimization schemes named OSP (structure parameters optimized process), OGP (gating system parameters optimized process), and OPP (processing parameters optimized process) are derived. Then a carbon emission prediction model is established to evaluate the effect of these schemes, and a sustainable manufacturing evaluation method with six indicators is also raised. Finally, a case study illustrates that 21%–24% of process carbon emission was saved after optimization on average. Among the strategies, OSP has the best energy-saving performance of average carbon emission, which is 4% lower than the others. OGP has the largest proportion of recyclable resources while OPP has the highest process yield and lowest adjustment cost. The results show that the proposed strategies can effectively improve the process yield, quality of casting, and decrease carbon emissions. The strategy raised in the paper supports the sustainable development of traditional manufacturing methods. [ABSTRACT FROM AUTHOR]

The widespread use of sand casting technology has brought tremendous pressure on the environment due to its energy consumption, waste discharge, and process related carbon emissions. A plan should begin at the design phase of the casting, in order to achieve low carbon sand castings or sand castings with low greenhouse gas emissions. Accurate prediction of carbon emission in sand casting is the basis for carbon emission reduction. To calculate and reduce carbon emission of sand castings during the sand casting process design phase, a low carbon process design method of sand casting based on process design parameters is proposed. The process design of sand casting includes various parameters. Three types of sand casting carbon source model were built by three categories of process design parameters analysis of sand mold casting. so as to predict the carbon emission of sand mold casting. The feasibility of the proposed method to estimating the carbon emission in the process design stage was validated by using a practical example. Through the comparison of the two process design schemes based on this method, it can be proved that carbon emissions have decreased significantly. Moreover, we can know the amount of carbon emissions from each type of carbon source can be predicted. A low carbon sand casting process during the sand casting process design phase can be created by this method. The optimization of process design parameters was useful to the reduce carbon emissions of the sand casting and benefited to achieve the aim of reach sustainable manufacturing. [ABSTRACT FROM AUTHOR]

Type 2 diabetes is considered to be one of the essential risks of adverse outcomes in coronavirus disease 2019 (COVID-19). 1 1 COVID-19, coronavirus disease 2019. Metformin and insulin were suggested to affect the outcomes. However, divergent views are still expressed. We aim to gain further insight into metformin and insulin in both pre-admission and in-hospital usage in COVID-19 patients with pre-existed type 2 diabetes. This is a multicentral retrospective study of the hospital confirmed COVID-19 patients between January 19 to April 09, 2020, who admitted to 3 main hospitals in Xiangyang city, China. The effect of type 2 diabetes, metformin, and insulin on COVID-19 were analyzed, respectively. Clinical characteristics, blood laboratory indices, clinical observational indices, and outcomes of these cases were collected. A total of 407 confirmed COVID-19 patients (including 50 pre-existed type 2 diabetes) were eligible in our study. COVID-19 patients with type 2 diabetes had more adverse outcomes than non-diabetes (OR 2 2 OR, odds ratio. : mortality: 1.46 [95% CI 3 3 CI, confidence intervals. 1.11, 1.93]; P < 0.001). Pre-admission metformin usage showed a declined intensive care unit admission rate in a dose-dependent fashion (OR 0.04 [95% CI 0.00, 0.99]; adjust P = 0.049). While in-hospital insulin usage attempted to increase the invasive ventilation (8 [34.8%] vs. 1 [3.7%], adjust P = 0.043), independent of age and blood glucose. Our study indicated that pre-admitted metformin usage may have beneficial effects on COVID-19 with pre-existed type 2 diabetes, insulin should be used sparingly in the hospital stay. [Display omitted] • Type 2 diabetes is the important risk factors of mortality and poor prognosis in COVID-19 patients. • Pre-admission metformin usage is associated with declining intensive care unit admission rate in a dose-dependent fashion. • In-hospital insulin usage had the risk of increasing invasive ventilation utilization. [ABSTRACT FROM AUTHOR]

• Established an effectiveness evaluation methods considering multiple aspects. • Research on traditional method, ink-jet bonding 3D printing and sand mold milling. • Detailed analysis and comparison of new technologies considering multiple aspects. • Better resource utilization rate of new technologies in the foundry industry. • Suitable for single or small batch production with better economic benefits. The emergence of new technologies has accelerated the process of sustainable development, gradually moving traditional manufacturing away from labor-intensive low-end towards high value-added and high-quality production. In order to study the application effectiveness of new technologies, the production of single or small batch castings in the traditional foundry industry is taken as the analysis object by using traditional manufacturing method, additive manufacturing (ink-jet bonding 3D printing) and subtractive manufacturing (sand mold milling), from the aspects of resources consumption, environmental impact and production efficiency. Among them, the resources consumption takes material, energy, and human resources into comprehensive consideration, while the environmental impact takes carbon emission as the main evaluation index, and the production efficiency is determined according to the actual casting output of the enterprise, this evaluation method is applicable to most of the traditional manufacturing industries. The results indicate that in the production of this kind of castings, additive and subtractive manufacturing have better resource utilization and significantly reduced the carbon emission of sand casting process by about 20.78% and 4.82%, respectively. Besides, the production efficiency of additive and subtractive manufacturing are 92.66% and 91.39% respectively, which has superiority not only in production capacity but also in economic benefits. According to the research conclusion, reference of what or whether new technologies can be used in traditional manufacturing to realize sustainability is provided, which has certain practical significance. [ABSTRACT FROM AUTHOR]