A novel series of composite hydrogels, built from the three components 1), hyaluronic acid methacryloyl (HAMA); 2), gelatin methacryloyl (GelMA), and 3), extracellular cartilage matrix (ECM), was ...prepared and studied regarding the possible utility in the surgical repair of damaged (perforated) tympanic membrane (TM). Noteworthy is component 3), which was harvested from the ribs of α-1,3-galactosidyltransferase-knockout (α-1,3 GalT-KO) pigs. The absence of α-1,3-galactosyl glycoprotein is hypothesized to prevent rejection due to foreign-body immunogenicity. The composite hydrogels were characterized by various aspects, using a variety of physicochemical techniques: aqueous swelling, structural degradation, behavior under compression, and morphology, e.g.,
biocompatibility was assessed by the CCK-8 and live-dead assays and through cytoskeleton staining/microscopy. Alcian blue staining and real-time PCR (RT-PCR) were performed to examine the chondrogenic induction potential of the hydrogels. Moreover, a rat TM defect model was used to evaluate the
performance of the hydrogels in this particular application. Taken together, the results from this study are surprising and promising. Much further development work will be required to make the material ready for surgical use.
Conductive hydrogels (CHs) for flexible bioelectronic devices have raised great attention due to their tunable mechanical performances, adhesion, anti‐swelling, and biocompatibility. This review ...summarizes the current development of conductive hydrogel‐based flexible bioelectronic devices in the aspect of classifications and applications. Firstly, the conductive hydrogels are classified into two kinds according to the types of conductivity: ionic conductive hydrogels and electronic conductive hydrogels (hydrogel based on pure conductive materials, introducing conductive micro/nano‐materials). Secondly, the applications of conductive hydrogels for bioelectronic device, like wearable devices (strain sensor, body fluid detector, serviced in extreme environment), tissue engineering (skin, heart, nerve, muscle), and other applications (bionic robot, cancer treatment), are highly illustrated. Finally, a depth outlook is given, which aims to promote the development of this field in the future.
This work reviews the recent progress of conductive hydrogels for bioelectronic devices from the aspect of classifications and typical applications. Furthermore, the current challenges and the corresponding strategies for the future development are in‐depth discussed, aiming to promote the practical application of conductive hydrogels in the fields of biomedicine and clinical medicine.
Abstract
Student information management is not only the basis of realizing efficient education and teaching management in Colleges and universities, but also an important link. However, in recent ...years, with the popular development of higher education, the number of students is further expanded, the number of students has increased a lot compared with the past, and the work of student information management has become increasingly heavy, which has brought new challenges to student information management. This requires managers (class teachers, class cadres) to update the concept of student management, innovate the student management mode, and use modern information technology to manage class affairs and student information. This topic is based on the realization of the standardization, digitization and automation of student information management, which can help class teachers and class cadres save manpower, material resources and financial resources, further improve the efficiency and accuracy of class information management in sports colleges and universities, strive to improve the scientific level of student information management, and provide a platform for students to broaden their horizons and actively participate in school activities. In this paper, through the design and development of sports information management system, and through the function and performance test, it is found that the system can meet the needs of colleges and universities, which simulates the results of 200 users’ concurrent number of operating system. The user concurrent number is the largest user concurrent number index of non functional requirements of the system, and the corresponding test items have passed the performance test requirements.
Pore structure characteristics of rock are a great concern for researchers and practitioners in rock mechanics and rock engineering fields. In this study, mercury intrusion porosimetry（MIP） was used ...to measure pore size distribution, as well as several important index parameters of pore structure, for seven common types of deep sedimentary rocks with a total of fifty rock samples. Results show a similar pore size distribution pattern of the rock samples in the same lithological group, but remarkable differences among different lithological groups. Among seven investigated rock types, mudstone has the smallest porosity of 3.37%, while conglomerate has the largest value of 18.8%. It is also found that the porosity of rock types with finer grain size is lower than those with coarser grain size. Meanwhile, a comparison of frequency distribution at ten intervals of pore-throat diameter among seven types of sedimentary rocks reveals that different rock types have different dominant pore-size ranges. Furthermore, permeability of the investigated sedimentary rock samples was derived based on MIP data using reported theoretical equations. Among seven rock types, mudstone has the lowest averaged permeability（3.64×10~（-6） mD） while conglomerate has the highest one（8.59×10~（-4） mD）. From mudstone to conglomerate, rock permeability increases with an increase of grain size, with only an exception of siltstone which has a relatively larger porosity value. Finally, regression analysis show that there is a good fitting（R~2=0.95） between permeability and porosity which could be easily used to derive reliable permeability values of similar kinds of engineering rocks.
Mid-life stage adults are at higher risk of developing venous thrombosis (VT)/thromboembolism (VT/E). Aging is characterized by an overproduction of reactive oxygen species (ROS), which could evoke a ...series of physiological changes involved in thrombosis. Here, we focus on the critical role of ROS within the red blood cell (RBC) in initiating venous thrombosis during aging. Growing evidence has shifted our interest in the role of unjustifiably unvalued RBCs in blood coagulation. RBCs can be a major source of oxidative stress during aging, since RBC redox homeostasis is generally compromised due to the discrepancy between prooxidants and antioxidants. As a result, ROS accumulate within the RBC due to the constant endogenous hemoglobin (Hb) autoxidation and NADPH oxidase activation, and the uptake of extracellular ROS released by other cells in the circulation. The elevated RBC ROS level affects the RBC membrane structure and function, causing loss of membrane integrity, and decreased deformability. These changes impair RBC function in hemostasis and thrombosis, favoring a hypercoagulable state through enhanced RBC aggregation, RBC binding to endothelial cells affecting nitric oxide availability, RBC-induced platelet activation consequently modulating their activity, RBC interaction with and activation of coagulation factors, increased RBC phosphatidylserine exposure and release of microvesicles, accelerated aging and hemolysis. Thus, RBC oxidative stress during aging typifies an ultimate mechanism in system failure, which can affect major processes involved in the development of venous thrombosis in a variety of ways. The reevaluated concept of the critical role of RBC ROS in the activation of thrombotic events during aging will help identify potential targets for novel strategies to prevent/reduce the risk for VT/E or VT/E recurrences in mid-life stage adults.
Abstract
Mechanical properties and geometries of printed products have been extensively studied in metal 3D printing. However, chemical properties and catalytic functions, introduced by metal 3D ...printing itself, are rarely mentioned. Here we show that metal 3D printing products themselves can simultaneously serve as chemical reactors and catalysts (denoted as self-catalytic reactor or SCR) for direct conversion of C1 molecules (including CO, CO
2
and CH
4
) into high value-added chemicals. The Fe-SCR and Co-SCR successfully catalyze synthesis of liquid fuel from Fischer-Tropsch synthesis and CO
2
hydrogenation; the Ni-SCR efficiently produces syngas (CO/H
2
) by CO
2
reforming of CH
4
. Further, the Co-SCR geometrical studies indicate that metal 3D printing itself can establish multiple control functions to tune the catalytic product distribution. The present work provides a simple and low-cost manufacturing method to realize functional integration of catalyst and reactor, and will facilitate the developments of chemical synthesis and 3D printing technology.
Offshore oil spills are of tremendous concern due to their potential impact on economic and ecological systems. A number of major oil spills triggered worldwide consciousness of oil spill ...preparedness and response. Challenges remain in diverse aspects such as oil spill monitoring, analysis, assessment, contingency planning, response, cleanup, and decision support. This article provides a comprehensive review of the current situations and impacts of offshore oil spills, as well as the policies and technologies in offshore oil spill response and countermeasures. Correspondingly, new strategies and a decision support framework are recommended for improving the capacities and effectiveness of oil spill response and countermeasures. In addition, the emerging challenges in cold and harsh environments are reviewed with recommendations due to increasing risk of oil spills in the northern regions from the expansion of the Arctic Passage.
•Offshore oil spills with impacts, policies and contingency planning were reviewed.•Newly developed monitoring and analysis methods for offshore oil spill were reviewed.•New technologies for offshore oil spill countermeasures were reviewed and summarized.•Methods in spill modeling and response decision support were reviewed with a proposed DSS.•Challenges in cold and harsh environments were summarized with recommendations.
•Comparing non-collaborative and collaborative financing strategies in a bilateral supply chain with capital constraints.•Generalizing bank financing separately strategy to the combining strategies ...composing of bank financing and supply chain internal credit.•Deriving the optimal operational and financing decisions under different strategies.•Examining the effect of guarantee ratio and supply chain's capital level.
We consider three kinds of financing strategies for a bilateral supply chain in which both the supplier and retailer are financially constrained. The three financing strategies are bank financing separately (BFS), bank financing with trade credit (BF-with-TC) and bank financing with the supplier's guarantee (BF-with-SG). The first one is regarded as a non-collaborative strategy, and the last two are regarded as collaborative strategies. By comparing the equilibrium decisions under the three financing strategies, we find that: (1) overall, collaborative strategies dominate non-collaborative strategy for the supplier and whole supply chain, whereas the reverse holds for the retailer; (2) BF-with-SG strategy performs the same as BFS strategy for all partners when the supplier provides no guarantee; (3) BF-with-SG strategy may outperform BF-with-TC strategy for the whole supply chain, depending on partners’ capital level as well as the supplier's guarantee ratio; (4) surprisingly, collaborative strategies do not necessarily result in less risk for the bank compared to non-collaborative strategy. Managerially, our results show that in some cases, all supply chain partners can perform better if the leader acts as a guarantor rather than as an intermediary creditor.
•Nonlinear pricing coupled with Revenue-sharing can coordinate the chain.•Further increase of direct sales cost and product substitution can profit both firms.•An encroaching supplier always hurts ...the retailer, even without direct sales.•A less powerful supplier is more likely to benefit from encroachment.•A powerful and relatively efficient supplier hurts from the threat of encroaching.
We explore the impact of nonlinear pricing (NP) on supplier encroachment in a supply chain, consisting of a retailer (he) and a supplier (she), who can sell through either the retailer, her direct channel, or both. The two channels’ products are imperfect substitutes. The firms bilaterally negotiate over the wholesale price and the quantity using NP. To better align their behaviors, they can implement revenue-sharing (RS) to share the retailer's sales revenue. Our analysis shows that NP coupled with RS coordinates the supply chain under encroachment when the supplier seizes all the retailer's sales revenue. In what follows, the supplier subsidizes the retailer's acquisition of products through a negative wholesale price. Surprisingly, further increase of the supplier's direct selling cost and product substitution degree can benefit both firms. Contrary to the prior research, the retailer always hurts from the supplier's ability to encroach, even when an inactive direct channel is introduced. Furthermore, a supplier with weak power is more likely to benefit from encroachment, but one with strong power hurts from initiating an inactive direct channel when her retail disadvantage is limited. Our main results are robust even after altering some assumptions in the basic model.
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