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Objective: The relationships between carotid intima-media thickness (C-IMT) and β cell function and insulin resistance in patients with type 2 diabetes (T2D) have not been fully elucidated. This study is to investigate whether impaired glucose metabolism is etiologically associated with C-IMT in patients with T2D. Methods: The study group consisted of 490 (284 men, 206 women) participants. Venous blood specimens were obtained from all subjects for biochemical profiles after an >8-h overnight fast. C-IMT was measured as the distance between the luminal-intimal leading edge (I-line) and the medial-adventitial leading edge (M-line) on the far wall. Insulin resistance was estimated with the homeostasis model assessment of insulin resistance (HOMA-IR). The acute insulin response to arginine was calculated as the mean of the three plasma insulin levels obtained within 2, 4, and 6 min after the arginine bolus minus the pre-stimulus plasma insulin levels. Results: There was a graded increase in C-IMT values according to tertiles of HOMA-IR in men; the values of C-IMT were significantly decreased across the tertiles of acute insulin and C-peptide responses in women. Multivariate analysis revealed that HOMA-IR and age were positively associated with C-IMT among men participants, and acute insulin response and current smoking were the independent determinants of C-IMT in women. Conclusion: Early insulin response stimulated by arginine is independently associated with C-IMT in women T2D individuals, whereas insulin resistance is positively correlated with C-IMT in men T2D subjects. [ABSTRACT FROM AUTHOR]

Peer-to-Peer (P2P) resource sharing promotes local resource-hungry task offloading to other mobile devices and balances the resource consumption between mobile devices. Most of existing P2P task offloading systems aims to solve the resource sharing between one pair exclusively without considering the cost of resource supply and the strategic behaviors of mobile users. In this paper, we propose two user models for the P2P task offloading system: honest user model and strategy user model. For the honest user model, we formulate the resource allocation maximization problem with latency and energy consumption constraints as an Integer Linear Programming. We show that the solution for honest user model can output 189% resource transactions of that for the strategic users. For the strategy user model, we propose a double auction-based P2P task offloading system, and design a truthful multi-resource transaction mechanism to maximize the number of resource transactions. We first group the mobile users based on the connected components to improve the efficiency of double auction. Then we utilize the McAfee Double Auction to price the resource transactions. Finally, we split each winning mobile user of double auction into multiple virtual mobile users, and use the matching approach to calculate the resource allocation. Through both rigorous theoretical analysis and extensive simulations, we demonstrate that the designed multi-resource transaction mechanism satisfies the desirable properties of computational efficiency, individual rationality, budget balance, truthfulness for resource request/supply, and general truthfulness for bid/ask price. [ABSTRACT FROM AUTHOR]

Device-to-device (D2D) communication is a core technology for expanding the next generation wireless cellular network. To deal with the security challenges and optimize the system communication quality, this paper investigates the security and efficiency problem of D2D underlay communication in a base station cell area with the presence of malicious eavesdroppers. Fairness and strategy space of both D2D User Equipment and Cellular User Equipment are taken into consideration under the control of Efficiency Functions. The optimization problems are formulated as a game model series of utility functions built on the unit price of jamming power and the amount of jamming service. We extracting the system into a price bargain game with a buyer and a seller both desiring maximum profits, a bargaining game approach is adopted to solve this problem by reaching an agreement of unit price. The step number of bargain process is also a restriction under consideration. For the non-steps model, an Evaluation Function and a Comprehensive Utility Function are demonstrated to analyze the bargain process. For steps-contained model, the step number of iteration is involved and an attenuation function is introduced to modify the bargaining game. The algorithms of two models are proposed to derive the equilibrium point for reaching an agreement. Finally, extensive simulations are illustrated for verifying proposed theory. [ABSTRACT FROM AUTHOR]

To balance and improve the resource utilization of the orthogonal frequency division multiple access (OFDMA) cellular networks, we switch parts of the edge users in overloaded cell to the adjacent light-loaded cells by using the inter-cell relay. The efficiency of traditional load balancing method based on the cell switching is low and in some cases, will occur the collision load problem. In this paper, we propose a new load balancing scheme based on inter-cell relay in downlink OFDMA cellular networks. Besides, we put forward a new spectrum division scheme to reduce interference and improve spectrum efficiency. According to the formulas derived from the model we established, we can obtain the signal interference ratio and further to calculate the amount of remaining subcarrier and the throughput of the system. Finally, through numerical calculation and simulation, the result shows that the load balancing and spectrum division schemes can remit the resource stress of the overloaded cell and improve the spectrum utilization in adjacent cells. [ABSTRACT FROM AUTHOR]

Mesenchymal stem cells (MSCs) have been increasingly tested in cell-based therapy to treat numerous diseases. Genetic modification to improve MSC behavior may enhance posttransplantation outcome. This study aims to test the potential therapeutic benefits of rat bone marrow MSCs overexpressing hypoxia-inducible factor 2α (rMSCsHIF-2α) in a rat hindlimb ischemia model. PBS, rMSCs, or rMSCsHIF-2α were injected into rat ischemic hindlimb. Compared with the injection of PBS or rMSCs, transplantation of rMSCsHIF-2α significantly improved blood perfusion, increased the number of vessel branches in the muscle of the ischemic hindlimb, and improved the foot mobility of the ischemic hindlimb (all P<0.05). rMSCHIF-2α transplantation also markedly increased the expression of proangiogenic factors VEGF, bFGF, and SDF1 and Notch signaling proteins including DII4, NICD, Hey1, and Hes1, whereas it reduced the expression of proapoptotic factor Bax in the muscle of the ischemic hindlimb. Overexpression of HIF-2α did not affect rMSC stemness and proliferation under normoxia but significantly increased rMSC migration and tube formation in matrigel under hypoxia (all P<0.05). RMSCsHIF-2α stimulated endothelial cell invasion under hypoxia significantly (P<0.05). Genetic modification of rMSCs via overexpression of HIF-2α improves posttransplantation outcomes in a rat hindlimb ischemia model possibly by stimulating proangiogenic growth factors and cytokines. [ABSTRACT FROM AUTHOR]

The concept of digital twin has been introduced for some time, yet one fundamental element of digital twin, digital material, has not been thoroughly studied. To interact with the physical product, the digital twin should always truthfully reflect the responses under various stimuli. In this paper, the deformation and fracture behavior of high impact polystyrene (HIPS) under the influencing factors of strain rate and stress triaxiality are studied to construct the material's digital model. A digital twin of air conditioner product is further built and tested under virtual drop test. Comparing to experimental results, the acceleration curve, crazing induced whitening and the fracture events can all be captured by the digital twin. Our work demonstrates the importance of material characterization as an essential step to construct an accurate digital twin and shows a promising future of digital twin in virtual testing to replace traditional "trial and error" experiments. [ABSTRACT FROM AUTHOR]

This study utilizes machine learning to analyze the recurrence risk of diabetic foot ulcers (DFUs) in elderly diabetic patients, aiming to enhance prevention and intervention efforts. The goal is to construct accurate predictive models for assessing the recurrence risk of DFUs based on high-risk factors, such as age, blood sugar control, alcohol consumption, and smoking, in elderly diabetic patients. Data from 138 elderly diabetic patients were collected, and after data cleaning, outlier screening, and feature integration, machine learning models were constructed. Support Vector Machine (SVM) was employed, achieving an accuracy rate of 93%. Experimental results demonstrate the effectiveness of SVM in predicting the recurrence risk of DFUs in elderly diabetic patients, providing clinicians with a more accurate tool for assessment. The study highlights the significance of machine learning in managing foot ulcers in elderly diabetic patients, particularly in predicting recurrence risk. This approach facilitates timely intervention, reducing the likelihood of patient recurrence, and introduces computer-assisted medical strategies in elderly diabetes management. [ABSTRACT FROM AUTHOR]

To review the clinic value and severity assessment of serum substance P (SP) concentration in children with different degrees of traumatic brain injury (TBI) through analyzing correlations with outcomes. One hundred thirty-nine children with TBI who were diagnosed and treated at Nanjing Medical University for longer than 72 hours between June 2017 and 2019 were analyzed. Blood samples were obtained within 24 hours after TBI to measure SP concentration. The endpoint was discharge mortality. Thirty healthy children composed the control group. Comparative analyses of differences in SP concentration were conducted for the different groups. Both the Sequential Organ Failure Assessment (SOFA) scores and Pediatric Clinical Illness Score (PCIS) were measured on admission and used in univariate and multivariate analyses. The serum SP (89.10 ± 64.32) pmol/L) level in the case group was significantly higher than that in the control group (21.84 ± 2.09) pmol/L (t = 5.71, P < 0.05). The serum SP (182.81 ± 58.39) pmol/L) level in the deceased group was significantly higher than that in the survival group (59.93 ± 27.90) pmol/L (t = 16.52, P < 0.05). A negative correlation existed between serum SP concentration and Glasgow Coma Scale score in the severe, moderate, and mild groups (r = −0.72, P < 0.05). Serum SP concentration was identified as an independent risk factor for mortality (odds ratio >1, 95% confidence interval = 1.04–1.28, P < 0.01). Receiver operating characteristic curve analysis suggested that serum SP concentration had the same calibrating power as SOFA and PCIS in discriminating the risk of death of children. Serum SP concentration was associated with severity in children with TBI, and extremely high levels indicated a poor prognosis. [ABSTRACT FROM AUTHOR]

The long noncoding RNA (lncRNA) gastric cancer associated transcript 3 (GACAT3) has been reported to play important roles in human tumorigenesis. However, its expression pattern, functions, and underlying mechanism in glioma remain unclear. In the present study, we showed that GACAT3 is upregulated in glioma tissues and cell lines. Through online databases, luciferase reporter assays and RNA immunoprecipitation (RIP) assays, we determined that GACAT3 acts as a competing endogenous RNA (ceRNA) for microRNA (miR)‐135a, which was downregulated and performed as a tumor inhibitor in glioma. Further, nicotinamide phosphoribosyl transferase (NAMPT) was confirmed as a target gene of miR‐135a by a series of gain‐ and loss‐of‐function assays. Overall, the present study was the first to show that GACAT3 regulates the expression of NAMPT to promote glioma progression by sponging miR‐135a. These findings provide a promising therapy strategy for glioma. GACAT3 was upregulated in glioma tissues and cell lines. GACAT3 promotes the proliferation, migration, and invasion of glioma cells by sponging miR‐135a and regulating NAMPT expression. [ABSTRACT FROM AUTHOR]

Background: New X-ray microangiography and third-generation synchrotron radiation-based micro-computed tomography have opened new perspectives for microvascular imaging of extremity. Here we aimed to visualize deep-level microvascular structure in rat hind limb by microangiographic technique, and compare images with those by conventional method. Materials and Methods: A total of 10 Sprague Dawley rats were used for in vivo and ex vivo study (five rats/group). Microangiography in vivo and ex vivo was performed and images were compared with those by conventional method. Synchrotron radiation-based micro-computed tomography (SRμCT) was also performed to reveal three-dimensional (3D) morphology of the blood vessel in rat hind limb. Results: By microangiographic technique, blood vessels in the rat limb could be clearly depicted with the minimum visualized blood vessel about 9 μm in diameter, and higher angiographic scores were achieved than those by conventional X-ray. In addition, the vascular network could be defined and analyzed at the micrometer scale from the 3D renderings of limb vessel as shown by SRμCT. Conclusions: Synchrotron radiation-based microangiography and SRμCT thus provided a practical and effective means to observe the microvasculature of limbs, which might be useful in assessment of angiogenesis in lower limbs. [ABSTRACT FROM AUTHOR]

• The trial vaccine was safe in subjects ≥ 3 years. • The immunogenicity of trial vaccine was non-inferior to the comparator in ≥ 3 years subjects. • Two-dose vaccine series with the trial vaccine is safe and can trigger a stronger immune response than that of one-dose in 3–8 years subjects. Subunit influenza vaccine only formulated with surface antigen proteins has better safety profiles relative to split-virion influenza vaccine. Compared to the traditional quadrivalent split-virion influenza vaccine, a novel quadrivalent subunit influenza vaccine is urgently needed in China. We completed a phase 3, randomized, double-blind, active-controlled, non-inferiority clinical study at two sites in Henan Province, China. Eligible volunteers were split into four age cohorts (3–8 years, 9–17 years, 18–64 years, and ≥ 65 years, based on their dates of birth) and randomly assigned (1:1) to the subunit and the split-virion ecNAIIV4 groups. All volunteers were intramuscularly administered a single vaccine dose at baseline, and children aged 3–8 years received a boosting dose at day 28. And the immune response was evaluated by measuring hemagglutinin-inhibition antibody titers against the four vaccine strains in blood samples. Safety profiles had nonsignificant differences between the study groups in ≥ 3 years cohort. Most adverse reactions post-vaccination, both local and systemic, were mild to moderate and resolved within 3 days. And no serious adverse events occurred. The immunogenicity of the trial vaccine was non-inferior to the comparator. Further, a two-dose vaccine series can provide better seroprotection than that of a one-dose series in children aged 3–8 years, with clinically acceptable safety profiles. Clinical Trials Registration. ChiCTR2100049934. [ABSTRACT FROM AUTHOR]

Mass spectrometry (MS) based analysis has received intense attention in diverse biological fields. However, direct MS interrogation of target biomolecules in complex biological samples is still challenging, due to the extremely low abundance and poor ionization potency of target biological species. Innovations in nanomaterials create new auxiliary tools for deep and comprehensive MS characterization of biomolecules. More recently, growing research interest has been directed to the compositional and structural engineering of nanomaterials for enriching target biomolecules prior to MS analysis, enhancing the ionization efficiency in MS detection and designing biosensing nanoprobes in sensitive MS readout. In this review, we mainly focus on the recent advances in the engineering of nanomaterials towards their applications in sample pre-treatment, desorption/ionization matrices and ion signal amplification for MS profiling of biomolecules. This review will provide a toolbox of nanomaterials for researchers devoted to developing analytical methods and practical applications in the biological MS field. [ABSTRACT FROM AUTHOR]

SUMMARY This paper investigates the problem of constructing a secret and reliable network coding communication scheme against an adversary that can reselect the μ tapping links in different time slices and inject z erroneous packets into the network, while the network suffers from ρ packet erasures. We first derive a necessary condition for keeping the transmitted information secret from the adversary, while the network is only subject to eavesdropping attack, and no errors are injected. We then provide two network coding schemes for error and erasure correction, which can decode the transmitted information correctly. With that, a secret and reliable network coding is proposed by combining two error and erasure correction schemes with secret communication. We show that under the requirement of 2 z + ρ+ μ < k ⩽2 z + 2 ρ communication can achieve a rate of k − μ− z − ρ packets, where k denotes the network capacity. Moreover, it ensures that the communicated information has complete reliability and information-theoretic security from the adversary. In particular, the requirement of packet length does not need to be sufficiently large, which is close to the practical packet length. Finally, we also compare our scheme's performance with existing work; the numeric results and security analyses illustrate the performance and security of our scheme. Copyright © 2011 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

SUMMARY The error control of random network coding has recently received a lot of attention because its solution can increase robustness and reliability of data transmission. To achieve this, additional overhead is needed for error correction. In this paper, we design a compressed error and erasure correcting scheme to decrease the additional overhead of error correction. This scheme reduces the computation overhead dramatically by employing an efficient algorithm to detect and delete linearly dependent received packets in the destination node. It also simplifies the hardware operations when the scheme reduces the received matrix Y to form E k( Y ) instead of E( Y ) in the decoding process. If at most r original packets get combined in k packets of one batch, the payload of one packet can increase from M − k to M − O( rlog q k) for the application of compressed code, where M is the packet length. In particular, the decoding complexity of compressed code is O( rm) operations in an extension field [ABSTRACT FROM AUTHOR]

Abstract Genetic diversity is the basic and most important component of biodiversity. It is essential for the effective conservation and utilization of genetic resources to accurately estimate genetic diversity of the targeted species and populations. This paper reports analyses of genetic diversity of a wild soybean population using three molecular marker technologies (AFLP, ISSR and SSR), and computer simulation studies of randomly selected subsets with different sample size (5-90 individuals) drawn 50 times from a total of 100 wild soybean individuals. The variation patterns of genetic diversity indices, including expected heterozygosity (He), Shannon diversity index (I), and percentage of polymorphic loci (P), were analyzed to evaluate changes of genetic diversity associated with the increase of individuals in each subset. The results demonstrated that (1) values of genetic diversity indices of the same wild soybean population were considerably different when estimated by different molecular marker techniques; (2) genetic diversity indices obtained from subsets with different sample sizes also diverged considerably; (3) P values were relatively more reliable for comparing genetic diversity detected by different molecular marker techniques; and (4) different diversity indices reached 90% of the total genetic diversity of the soybean population quite differently in terms of the sample size (number of individuals) analyzed. When using the P value as a determinator, 30-40 individuals could capture over 90% of the total genetic diversity of the wild soybean population. Results from this study provide a strong scientific basis for estimating genetic diversity and for strategic conservation of plant species. [ABSTRACT FROM AUTHOR]

The recent development of human-carried mobile devices has promoted the great development of mobile crowdsensing systems. Most existing mobile crowdsensing systems depend on the crowdsensing service of the deep cloud. With the increasing scale and complexity, there is a tendency to enhance mobile crowdsensing with the edge computing paradigm to reduce latency and computational complexity, and improve the expandability and security. In this paper, we propose an integrated solution to stimulate the strategic users to contribute more for truth discovery in the edge-assisted mobile crowdsensing. We design an incentive mechanism consisting of truth discovery stage and budget feasible reverse auction stage. In truth discovery stage, we estimate the truth for each task in both deep cloud and edge cloud. In budget feasible reverse auction stage, we design a greedy algorithm to select the winners to maximize the quality function under the budget constraint. Through extensive simulations, we demonstrate that the proposed mechanism is computationally efficient, individually rational, truthful, budget feasible and constant approximate. Moreover, the proposed mechanism shows great superiority in terms of estimation precision and expandability. [ABSTRACT FROM AUTHOR]

Summary: The emergence of fog computing facilitates industrial Internet of Things (IIoT) to be more real‐time and efficient; in order to achieve secure and efficient data collection and applications in fog‐assisted IIoT, it usually sacrifices great computation and bandwidth resources. From the low computation and communication overheads perspective, this paper proposes a layered data aggregation scheme with efficient privacy preservation (LDA‐EPP) for fog‐assisted IIoT by integrating the Chinese remainder theorem (CRT), modified Paillier encryption, and hash chain technology. In LDA‐EPP scheme, the entire network is divided into several subareas; the fog node and cloud are responsible for local and global aggregations, respectively. Specially, the cloud is able to obtain not only the global aggregation result but also the fine‐grained aggregation results of subareas, which enables that can provide fine‐grained data services. Meanwhile, the LDA‐EPP realizes data confidentiality by the modified Paillier encryption, ensures that both outside attackers and internal semi‐trusted nodes (such as, fog node and cloud) are unable to know the privacy data of individual device, and guarantees data integrity by utilizing simply hash chain to resist tempering and polluting attacks. Moreover, the fault tolerance is also supported in our scheme; ie, even though some IIoT devices or channel links are failure, the cloud still can decrypt incomplete aggregation ciphertexts and derive expected aggregation results. Finally, the performance evaluation indicates that our proposed LDA‐EPP has less computation and communication costs. [ABSTRACT FROM AUTHOR]

Composite insulators in valve tower of UHVDC converter station withstand combined ac-dc voltage. The flashover performance of silicone rubber under combined voltage is investigated in this paper. The voltages on the post insulator of valve tower under different operating conditions are simulated in PSCAD/EMTDC, and the harmonic components of the voltages are analyzed. The simulation results indicate that the ac frequencies of the voltage on the post insulator are mainly 50 Hz, 3n and 6n±1 times harmonics. The flashover voltages of silicone rubber under different combinations of ac and dc voltages are tested, including different single frequency ac voltages superimposed on different dc voltages, and different combined harmonic voltages superimposed on different dc voltages. The test results indicate that different ratios of dc voltage to ac voltage and different percentages of harmonics have various influences on the flashover voltage of silicone rubber. Moreover, argon atmosphere pressure plasma jet (Ar APPJ) is applied to modify the surface of the silicone rubber under different modification times and voltages. The flashover voltages and the surface morphologies of the silicone rubber before and after surface modification are compared. Surface modification by Ar APPJ can improve the surface resistivity of the silicone rubber significantly, and the flashover voltage also increases. [ABSTRACT FROM AUTHOR]

Thyristors of valve tower in converter station are controlled through fiber. Valve fiber withstands strong electric field and harmonic voltage. Partial discharge (PD) and flashover faults sometimes happen in valve tower. In this paper, flashover test is conducted for different fiber sheath materials under different voltage types (DC voltage and harmonic voltage superimposed on DC voltage). PD characteristics of fiber under combined voltage of AC voltage and DC voltage are measured. And influence of sheath materials on the PD inception voltage is discussed. Test results indicate that the flashover voltages of fiber sheath materials are different under different voltage types. Sheath material with higher surface resistivity has higher flashover voltage under DC voltage. Moreover, PD of fiber under vertical electric field concentrates on the falling edge of the positive half-circle of the AC voltage, and the PD strengthens with the increase of DC voltage. And the sheath material whose ratio of volume resistivity to relative dielectric constant is approximate to that of the fiber body (SiO2), has higher PD inception voltage. [ABSTRACT FROM AUTHOR]

As the spatial and temporal correlations of sensor readings are common in wireless sensor networks, motivated by these features and the drawbacks of network coding (NC), we introduce compressed sensing (CS) into NC scheme and construct a cooperating coding mechanism, which performs over different data fields with a compatible transformation measure for the combination of NC and CS. This cooperating coding scheme can reduce the amount of redundant information transmission significantly, because the temporal and spatial correlations are explored fully. Meanwhile, the erasures and errors are considered simultaneously in relay transmission process; a NC decoding for error control is proposed to correct the erasures and errors. Although the decoding error of NC is existent, this error can be further reduced by the reconstruction process of CS; as a result, the relative recovery error is small enough in the sink. Finally, the reliability and performance analyses confirm that the proposed cooperating coding scheme obtains considerable compression gain as compared with conventional coding scheme of NC and transmits information reliably with high recovery precision. Copyright © 2014 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Abstract: Electrospun blended nanofibrous scaffolds were fabricated from an synthetic biodegradable polymer (poly(ethylene carbonate-ɛ-caprolactone) (poly(EC-CL)) and vascular endothelial growth factor with different weight ratios. Results showed that the diameter of blended scaffolds was 440±55nm. VEGF on the surface of the blended scaffolds was identified by immunofluorescence. In vitro cell proliferation, viability assay results showed that human umbilical vein endothelial cells (HUVECs) had a good growth and spread morphology on the blended scaffolds. Scaffolds electrospun from this polymer contained VEGF had a good application in tissue engineering. [Copyright &y& Elsevier]

Abstract: The use of current drug-loaded vascular scaffolds is limited in sustained drug release and stability studies in clinical and preclinical trials. We found that poly(l-glutamic acid)-b-poly(propylene oxide)-b-poly(l-glutamic acid) (PLGA-b-PPO-b-PLGA) triblock copolymers can deliver multiple poorly water-soluble drugs (e.g., Paclitaxel) at clinically relevant doses. In this study, we synthesized a new drug-loaded vascular external graft with electrospun nanofibrous scaffolds [poly(l-lactide-co-ɛ-caprolactone) (PLCL):fibrinogen; 2:1 (w/w)] and drug-loaded PLGA-b-PPO-b-PLGA micelles. Cell proliferation and viability assay results showed that beagle smooth muscle cells grew well on the surface of vascular graft-coated micelles at a percentages of 10% (w/w) GPG:PLCL–fibrinogen. This study demonstrates that micelle-coated electrospun PLCL–fibrinogen vascular scaffolds have potential applications in vascular tissue engineering. [Copyright &y& Elsevier]

The laser-induced choroidal neovascularization (CNV) mouse model, as the most classic animal model of age-related macular degeneration (AMD), has been widely used. We designed a hand-held mouse holder to optimize mouse fixation in the laser-induced CNV modelling process, which was inconvenient until now. This study aimed to evaluate the effectiveness of our in-house hand-held mouse holder design in the laser-induced CNV mouse modelling process. Six ophthalmic residents were invited to perform laser-induced CNV mouse modelling by hand or using the holder. We compared the learning time of residents and their physical and mental fatigue with the two methods. In addition, we compared the parameters of CNV modelling with two methods by a skilled operator, including the time of photocoagulation, induction rate and uniformity of CNV lesions. In the learning phase, the average learning time to master the modelling method was significantly shortened by utilizing the holder. The fatigue in the operation process was quantified to a level from 0 to 4, and the physical fatigue by using holder (0.8 ± 0.3) was lower than by hand (2.6 ± 0.4), and the mental fatigue was relieved from 2.3 ± 0.5 to 0.4 ± 0.3. On the other hand, the skilled operator can significantly shorten the time of laser photocoagulation from 146.7 ± 36.0 s to 63.6 + 5.7 s and improve the success rate of modelling from 50.0% ± 8.3%–87.5% ± 6.7% by using a holder compared to hand. In addition, the standard error of the mean (SEM) of the distance between the CNV lesion and the optic nerve (ON) and the distance between each lesion was reduced. This hand-held mouse holder could optimize the setting and conditions of laser-induced CNV mouse modelling by improving the learning curve, reducing fatigue, shortening the time for photocoagulation, improving the success rate and consistency of laser-induced lesions. [ABSTRACT FROM AUTHOR]

Abstract: Spray-dried sintered Al2O3-13wt. %TiO2 powders were directly coated on Ti-6Al-4V alloy by coaxial laser cladding. The microstructure, elements distribution and phase analysis of the cladding sample were studied by optical microscopy, EPMA, SEM and XRD methods. The results indicated that the coatings with fine metallurgical bonding to the substrate comprised major stable α-Al2O3 and demonstrated three different regions of solidification microstructures. One region, at the bottom of the molten pool, contained mainly Ti enrichment columnar grains and randomly scattered ceramic particles, named Transition Zone. The second region, within the 0.1mm scope above the transition zone, contained mainly fine equiaxed Al2O3 grains. The third region, at the upper zone of the molten pool, showed coarse equiaxed and cellular Al2O3 grains with obvious segregation of Ti and V elements. The mechanisms of microstructure formation, elements migration and segregation in the experiment were discussed. [Copyright &y& Elsevier]