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One common cause of vision loss after retinal detachment surgery is retinal scarring. Here the authors demonstrate that a bio-functional polymer can prevent retinal scarring by suppression of epithelial-mesenchymal transition and hyper-proliferation of retinal pigment epithelial cells.

Abstract For a certain kind of decision event, the decision maker does not know the internal mechanism and knowledge information of the decision events.When this kind of decision events gives multiple selection branches, it is found that there is a decision psychological tendency to find the most common features by comparing the selection branches. Based on this, a zero-knowledge decision making (ZKDM) method is proposed. By defining the feature points and feature sets of the selection branches of the decision events, the characteristic moments of the system are constructed and the branch with the most common characteristics is obtained. It is observed that through the findings of investigation the probability of arriving at the correct choice based on the ZKDM method is high. The effectiveness of the ZKDM method may be related to the fact that the designers of decision events usually determine the correct selection branch first, before changing it to design other branches. A questionnaire survey of 279 respondents reveals that more than half of them actually adopt such a design idea. Furthermore, a separate questionnaire survey of 465 decision-makers reveal that 19.14% of the respondents clearly adopt ZKDM.

This review paper provides the conceptualization and development of augmented reality (AR) environment for education by featuring implementations in physics education. The use of AR creates an environment designed to fully incorporate next-generation AR-aided notes, virtual laboratory and interactive problem-based learning with real-time automated generation of application-centric scenarios. This can be carried out via the fusion and technologizing of pre-existing teaching materials (such as books and notes) using AR and be mobile device friendly to fully leverage on learning beyond classrooms. Such a method is proposed to give students the access to resources anytime, anywhere without the spatial and temporal restrictions of synchronous-learning. This review discusses the advances of AR as an important tool in physics education, identify potential challenges and envisions the future by surveying recent trends and reviews. We provide perspective on practical AR implementation and evaluation for educators and school administrator, and potential academic advances through physics education research for researchers.

Augmented reality and virtual reality, collectively called extended reality (XR), has made substantial strides in the education sector in both theory and practice. Existing active research focuses on implementation by educators to teach real-world phenomena, and for students to learn through an immersive experience. This article surveys existing research in XR with special focus on the implications of immersive extended realities for teaching and learning engineering mathematics in institutes of higher learning. We also survey various interactive multimedia associated with XR before examining the implications of XR as an educational tool for existing mathematics pedagogy. Finally, the contribution of this scoping review is to provide an adaptable framework on XR implementation for educators, and potential academic advances for researchers.

Abstract Background Dormancy is widespread in nature, but while it can be an effective adaptive strategy in fluctuating environments, the dormant forms are costly due to the inability to breed and the relatively high energy consumption. We explore mathematical models of predator-prey systems, in order to assess whether dormancy can be an effective adaptive strategy to outcompete perennially active (PA) prey, even when both forms of the dormitive prey (active and dormant) are individually disadvantaged. Results We develop a dynamic population model by introducing an additional dormitive prey population to the existing predator-prey model which can be active (active form) and enter dormancy (dormant form). In this model, both forms of the dormitive prey are individually at a disadvantage compared to the PA prey and thus would go extinct due to their low growth rate, energy waste on the production of dormant prey, and the inability of the latter to grow autonomously. However, the dormitive prey can paradoxically outcompete the PA prey with superior traits and even cause its extinction by alternating between the two losing strategies. We observed higher fitness of the dormitive prey in rich environments because a large predator population in a rich environment cannot be supported by the prey without adopting an evasive strategy, that is, dormancy. In such environments, populations experience large-scale fluctuations, which can be survived by dormitive but not by PA prey. Conclusion We show that dormancy can be an effective adaptive strategy to outcompete superior prey, recapitulating the game-theoretic Parrondo’s paradox, where two losing strategies combine to achieve a winning outcome. We suggest that the species with the ability to switch between the active and dormant forms can dominate communities via competitive exclusion.

Biceps tenotomy (BT) is a common surgery used to address anterior shoulder pain and joint dysfunction in humans. Using animal models to simulate human conditions is an effective and essential research strategy to further understand histologic and biomechanical processes that occur after BT, including the pathology of the detached biceps, secondary tendinopathic conditions of the rotator cuffs, and glenohumeral functional changes. This Technical Note presents a comprehensive step-by-step description of an arthroscopic BT procedure in rabbits. This technique is particularly beneficial, as the mini-invasive arthroscopic technique in a rabbit model is similar to that performed in humans. which resulted in less scarring and injuries to other adjacent structures in comparison with open surgery.

Understanding the pathophysiology of rotator cuff tears (RCTs) in animal models is of great importance, as it helps in the development of repair strategies and therapeutic treatments for rotator cuff diseases in humans. This Technical Note describes a comprehensive step-by-step description of an arthroscopic-assisted minimally invasive RCT model in rabbits. This technique is beneficial because the rabbit has rotator cuffs anatomically similar to those of humans, and it has been widely used as a preclinical animal model in the basic science literature. Compared with other small animals (e.g., mice and rats), the advantage of the rabbit model is that it can test the effectiveness and healing process of new surgical repair techniques that require relatively larger anatomical structures. Moreover, it is more cost-effective compared with larger animal models, such as sheep and canines. This arthroscopic-assisted mini-invasive technique to create an RCT model may have a better effect on simulating the degenerative and chronic RCT state in humans than the commonly used open surgery, along with an earlier return to activities, less scarring and tissue adhesion, fewer injuries to the deltoid, and fewer complications.

The peridynamic (PD) theory is based on nonlocal mechanics and employs particle discretization in its computational domain, making it advantageous for simulating cracks. Consequently, PD has been applied to simulate ice damage and ice–structure interaction under various conditions. However, the calculation efficiency of PD, similar to other meshless methods, is constrained by the number of particles and the inherent limitations of the method itself. These constraints hinder its potential for further development in the field of ice−structure interaction. This study aims to explore the computational efficiency of various methods that can be employed to improve the computational cost of PD in ice–structure interactions. Specifically, we analyze the computational efficiency of three different methods (the MPI parallelization, the updated link−list search method, and the particle−pair method) and their collaborative calculation efficiency to reduce simulation time. These methods are employed to calculate ice–ship interaction, and their coupled efficiency is studied. Furthermore, this study discusses the computation strategy to improve efficiency on using the PD method to calculate ice–structure interaction. The present work provides scholars who employ PD to calculate ice–structure interaction or ice damage with a referential discussion plan to achieve an efficient numerical computation process.

The Shadongnan structural zone in the western Bohai Sea area is located in the transitional position from the Shaleitian uplift to the Sha'nan sag. Due to the influence of various factors such as inherited uplift, syn-depositional faults and ancient valleys in different periods, the development of sedimentary facies is relatively complex, restricting the further oil and gas exploration and development. We restored the ancient landform of each three-level sequence in the Dongying formation in the sedimentary period using the strata thickness method, identifying uplifts, slopes, ancient valleys, fault troughs, and shallow and deep sub-sags in the study area. Meanwhile, there are two kinds of ancient landform in the Shadongnan structural zone bounded by the NNE-trending transform fault, with the valley-paleoslope-fault slope-break in the west and the valley-multistage fault slope-break in the east. The former is composed of eroded valleys, buried hill slopes and early syn-depositional faults, while the latter eroded valleys and two or three syn-depositional faults with the same direction and different periods. Our study showed that the valleys located at the edge of the uplifts were the source channels in the early stage and filled with sediments in the late stage. The distribution and filling of the sedimentary system of the valley-paleoslope-fault slope-break were mainly controlled by the ancient slope-fault slopes, and the syn-depositional faults controlling the fault slopes were relatively active in the Shahejie formation and controlled the deposition and filling of the lowstand fans and turbidite fans. By the SQ-Ed3 period, the fault activities gradually weakened, and the fault slope-break distinct the fan delta plain and front in SQ-Ed3 from the deposition of the braided river delta front and shallow lake in SQ-Ed2d and SQ-Ed2u. The Shadongnan No.1 syn-depositional fault with the valley-multistage fault slope-break, which was developed and activated in SQ-Ed3, controlled the formation of the deep sub-sags and the development of the small fan deltas under the first slope break. The Sha'nan syn-depositional fault both formed and activated in SQ-Ed2d was acted as the second slope break separating the bulges and slopes, and controlled the depositional filling of the small fan delta in SQ-Ed2d.

In order to study the stability of cefuroxime axetil acetone solution, by using high-performance liquid chromatography, the single factor test was conducted to study the variation ofcefuroxime axetilcontent in the solution with time under different conditions such as the initial solution pH, temperature and oxidant species. The chemical reaction kinetics method was used to establish the degradation reaction kinetics models of cefuroxime axetil under different conditions. The model parameters were obtained by regression, and the half-life(t1/2) was predicted. The degradation mechanism of cefuroxime axetil was analyzed from the molecular scale by Materials Studio simulation software. The results show that the degradation of cefuroxime axetil acetone solution under the above conditions is in line with the first-order reaction kinetics. When pH is lower than 9.54, cefuroxime axetil acetone solution is basically stable. When pH is higher than 9.54, the chemical stability of cefuroxime axetil acetone solution becomes worse, the degradation rate increases rapidly, and the color of the solution becomes darker with the increase of pH value. The chemical stability of cefuroxime axetil acetone solution decreases with the increase of temperature. The research result provides data support for production process, crystallization process design, storage and application.

A new structure of underactuated manipulator is proposed to meet the need of multi-functional end fixture of robot. The most innovative point of the manipulator is that its end knuckle is completely passive envelope， which improves the grasping stability. The grasping attitude analysis and stability analysis are carried out， the feasibility of the scheme is verified， and the grasping attitude of different objects is verified. The prospect of the control strategy research is put forward.