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Planetary rovers have played significant roles in exploring potential landing sites on Mars and the moon, and they will continue to work as one of the most effective tools for future planetary missions. Sample acquisition for on-site analysis and possible return to earth is one of the most challenging and promising missions for planetary exploration. The Kapvik microRover is a smart, reconfigurable all-terrain multimission microRover prototype that was developed to address the challenges of planetary exploration and sample acquisition. The Kapvik microRover consists of a mobile platform, an onboard robotic mast, and a number of scientific sensors. This article presents the development of the Kapvik robotic mast, which combines a robotic arm and microRover mast, delivering both of their functions. Namely, the innovative robotic mast can perform sample acquisition and transfer for storage as well as assist the microRover in navigation and inspection. To satisfy the stowage requirements and provide triangular support for the navigation cameras, a novel locking mechanism and associated control techniques are designed to enable self-locking and unlocking of the robotic mast. A prototype has been developed for the Canadian Space Agency, and extensive experiments have been conducted to validate the proposed design. [ABSTRACT FROM AUTHOR]

• An integrated, flexible, economical and considerate bridging strategy is proposed. • The strategy can effectively cope with the sudden drop in metro reliability. • To be more realistic, the strategy considers hindered passengers' heterogeneity. • A bi-level programming model is established to describe the strategy. • The strategy has remarkable superiority in comparing delay and response time. With the frequent occurrence of metro disruption, how to guarantee the reliability of the system has gradually become a research hotspot. Previous studies mostly used the bridging bus to maintain the service level, and ignored the experience of passengers, the reliability of conventional bus system, the heterogeneity of passenger and underutilized the capacity. Hence, to deal with the deficiencies, a comprehensive bridging strategy is proposed to balance the benefit of stranded metro passengers and conventional bus passengers considering the dynamic changes in passenger demand. We develop a tailor-made integration framework for operators, dispatch bridging buses from multiple alternative sources, and design two operated access methods: Station-Station docking method and demand-responsive method to satisfy the heterogeneity of passenger. A bi-level programming model is established to describe the strategy and to determine operation scheme. And then, a two-layer multi-objective genetic algorithm is used to solve the bi-level model. A case study is conducted based on the real case of Guangzhou Metro disruption in 2019. The superiority of the proposed strategy over the two benchmark strategies is demonstrated by the results. Notably, the study provides some suitable and operable evacuation strategy for transit operators to guarantee residents' daily travel plan with the sensitivity analysis. [ABSTRACT FROM AUTHOR]

FGFR3 kinase mutations are associated with a variety of malignancies, but FGFR3 mutant inhibitors have rarely been studied. Furthermore, the mechanism of pan-FGFR inhibitors resistance caused by kinase domain mutations is still unclear. In this study, we try to explain the mechanism of drug resistance to FGFR3 mutation through global analysis and local analysis based on molecular dynamics simulation, binding free energy analysis, umbrella sampling and community network analysis. The results showed that FGFR3 mutations caused a decrease in the affinity between drugs and FGFR3 kinase, which was consistent with the reported experimental results. Possible mechanisms are that mutations affect drug-protein affinity by altering the environment of residues near the hinge region where the protein binds to the drug, or by affecting the A-loop and interfering with the allosteric communication networks. In conclusion, we systematically elucidated the underlying mechanism of pan-FGFR inhibitor resistance caused by FGFR3 mutation based on molecular dynamics simulation strategy, which provided theoretical guidance for the development of FGFR3 mutant kinase inhibitors. [ABSTRACT FROM AUTHOR]

Semi-autonomous control schemes can address the limitations of both teleoperation and fully autonomous robotic control of rescue robots in disaster environments by allowing a human operator to cooperate and share such tasks with a rescue robot as navigation, exploration, and victim identification. In this paper, we present a unique hierarchical reinforcement learning-based semi-autonomous control architecture for rescue robots operating in cluttered and unknown urban search and rescue (USAR) environments. The aim of the controller is to enable a rescue robot to continuously learn from its own experiences in an environment in order to improve its overall performance in exploration of unknown disaster scenes. A direction-based exploration technique is integrated in the controller to expand the search area of the robot via the classification of regions and the rubble piles within these regions. Both simulations and physical experiments in USAR-like environments verify the robustness of the proposed HRL-based semi-autonomous controller to unknown cluttered scenes with different sizes and varying types of configurations. [ABSTRACT FROM PUBLISHER]

BACKGROUND Uterine smooth muscle tumors (USMTs) constitute a group of histologic, genetic, and clinical heterogeneous tumors that include at least 6 major histologically defined tumor types: leiomyoma (ULM), mitotically active leiomyoma (MALM), cellular leiomyoma (CLM), atypical leiomyoma (ALM), uncertain malignant potential (STUMP), and leiomyosarcoma (LMS). Apart from ULM and LMS, the nature of these variants is not well defined. METHODS A total of 167 cases of different USMT variants were collected, reviewed, and diagnostically confirmed based on the World Health Organization and Stanford schemes. These included 38 cases of LMS, 18 cases of STUMP, 42 cases of ALM, 22 cases of CLM, 7 cases of MALM, and 40 cases of ULM. Molecular analysis included selected microRNAs (miRNAs), oncogenes, and tumor suppressors that are highly relevant to USMT. RESULTS Overall, 49% (17/35) of LMS cases and 7% (1/14) of STUMP cases died due to their USMT, but no deaths were attributed to ALM. miRNA profiling revealed that ALM and LMS shared similar miRNA signatures. P53 mutations and PTEN deletions were significantly higher in LMS, ALM, and STUMP compared with other USMT variants ( P < .01). In contrast, MED12 mutations were extremely common in ULM and MALM (>74%) but were significantly less common (<15%) in CLM, ALM, STUMP, and LMS ( P < .01). CONCLUSION Six types of USMT have different gene mutation fingerprints. ALM shares many molecular alterations with LMS. Our findings suggest that ALM may be a precursor lesion of LMS or have similar genetic changes during its early stage. Cancer 2014;120:3165-3177. © 2014 American Cancer Society. [ABSTRACT FROM AUTHOR]

Background: The zinc finger protein A20 is an important negative regulator of inflammation; polymorphisms in the corresponding gene, TNFAIP3, have been reported to be associated with several inflammation diseases. However, only a few studies have focused on the relationship between TNFAIP3 polymorphisms and acute pancreatitis (AP). Methods: We enrolled 201 healthy controls and 190 acute pancreatitis patients (including 47 systemic inflammatory response syndrome patients) for this study and used DNA sequencing to investigate polymorphisms in the TNFAIP3 promoter. The functional effects of these variants on transcriptional activity, A20 expression, NF-κB activity, and TNF-α and IL-1β levels, after in vitro lipopolysaccharide stimulation, were assessed. Results: Two SNPs (rs59693083 and rs5029924) in the TNFAIP3 promoter were selected based on bioinformatic analysis. Neither of these SNPs was associated with susceptibility to AP; however, acute pancreatitis patients who possessed the T allele of rs5029924 were more likely to experience systemic inflammatory response syndrome. Moreover, rs5029924 was found to affect TNFAIP3 promoter activity. After lipopolysaccharide stimulation, the expression of A20 protein significantly decreased, while the activity of NF-κB and the production of TNF-α and IL-1β significantly increased in whole blood leukocytes from subjects with the T allele. Conclusion: The rs5029924 polymorphism in the TNFAIP3 promoter may alter the risk of systemic inflammatory response syndrome in acute pancreatitis patients by influencing the expression of A20 protein. [ABSTRACT FROM AUTHOR]

Baseline Characteristics and Prognosis of LS-AF Patients Background It is unknown if baseline characteristics and prognosis of patients with longstanding persistent (defined as history greater than 1 year) atrial fibrillation (LS-AF) differ among those with either recurrent atrial tachycardia (R-AT) or recurrent AF (R-AF) after first ablation. Methods In 222 consecutive LS-AF patients treated for R-AT or R-AF after first ablation, activation and entrainment mapping was used to identify R-AT mechanism and to guide the following ablation, and the ablation endpoints for all patients included complete pulmonary vein isolation, bidirectional block of lines, and disappearance of complex fractionated atrial electrograms. Results There were 102 patients in the R-AF group. LS-AF patients with R-AT as compared to R-AF had shorter AF duration and recurrence interval, smaller left atrium size and left ventricular end-diastolic diameter, and less mitral and aortic regurgitation before first ablation. During follow-up (17.7 ± 4.0 months) after R-AT/R-AF ablation, 78 LS-AF patients developed recurrent atrial tachyarrhythmia, with lower overall and recurrence as AF in R-AT versus R-AF groups. Conclusions LS-AF patients who develop R-AT versus R-AF after first ablation have more favorable baseline characteristics and prognosis. [ABSTRACT FROM AUTHOR]

Robotic urban search and rescue (USAR) is a challenging yet promising research area which has significant application potentials as has been seen during the rescue and recovery operations of recent disaster events. To date, the majority of rescue robots used in the field are teleoperated. In order to minimize a robot operator’s workload in time-critical disaster scenes, recent efforts have been made to equip these robots with some level of autonomy. This paper provides a detailed overview of developments in the exciting and challenging area of robotic control for USAR environments. In particular, we discuss the efforts that have been made in the literature towards: 1) developing low-level controllers for rescue robot autonomy in traversing uneven terrain and stairs, and perception-based simultaneous localization and mapping (SLAM) algorithms for developing 3D maps of USAR scenes, 2) task sharing of multiple tasks between operator and robot via semi-autonomous control, and 3) high-level control schemes that have been designed for multi-robot rescue teams. [ABSTRACT FROM AUTHOR]

Purpose: Although several techniques for modification of atrial fibrillation (AF) substrate, such as linear ablation and complex fractionated atrial electrograms (CFAEs) ablation, have been proposed for longstanding persistent AF (LS-AF) and improved the outcome, there was still a certain recurrence rate, even if current ablation endpoints of these techniques were completely achieved. The purpose of this study was to describe the determinants of recurrent AF in patients who obtained current ablation endpoints with LS-AF. Methods and results: In all, 208 consecutive patients who obtained current ablation endpoints with LS-AF were studied. The current ablation endpoints were defined as complete pulmonary vein isolation, bidirectional block of lines, and disappearance of CFAEs. After a follow-up of 19.9 ± 4.1 months, the patients were classified as AF recurrence group and non-AF recurrence group (including patients with sinus rhythm and atrial tachycardia), and 34 (16 %) patients were in the AF recurrence group. The patients in AF recurrence group had higher rates of right atrium (RA) enlargement (67.7 vs. 45.4 %, p = 0.018) and ≥2 procedure times (58.8 vs. 27.0 %, p < 0.001), longer AF duration (82.4 ± 44.8 vs. 50.8 ± 42.8 months, p < 0.001), and larger left atrium (LA) diameter (49.4 ± 6.2 vs. 46.5 ± 5.3 mm, p = 0.007). In the multivariate analysis, RA enlargement, ≥2 procedure times, and AF duration were independent predictors of AF recurrence. Conclusion: RA enlargement, ≥2 procedure times, and AF duration played important roles in AF recurrence in patients who obtained current ablation endpoints. For these patients with AF recurrence who had already underwent ≥2 procedure times, enlarged RA may contribute to other AF foci and/or substrate, and the ablation strategy may be transformed from LA to RA in the next ablation procedures. [ABSTRACT FROM AUTHOR]

Highlights: [•] Evidence of Holocene activity had not previously been found along the YYF. [•] We found a 70-km-long surface scarp in Heilongjiang Province and a 20-km-long scarp in Jilin Province along the YYF. [•] The trenches across these two scarps reveal fault displacement 14C dates of 1730±40 and 4410±30years BP. [•] The kinematics of the YYF is dextral strike-slip with a normal component. [ABSTRACT FROM AUTHOR]

Abstract: This paper presents the multiple mode control system of a compact wrist, which can work in active mode with position or torque control, or passive mode with wrist-environment interactive force compensation. Passive mode is realized without using mechanical solutions such as a clutch, which not only saves weight and volume of the wrist, but also avoids losing track of the joints’ position while switching from passive mode to active mode. The objective is to make the wrist suitable for dexterous manipulation in unstructured environments, such as door opening. A robust adaptive controller is developed for tracking control of the wrist in active mode; and a new interactive force compensation technique is proposed based on force sensor measurement, to enable passive working mode of the compact wrist. A prototype wrist has been developed and experiments have been conducted to validate the proposed design and algorithms. [Copyright &y& Elsevier]

Impact of COPD on Atrial Fibrillation Ablation. Background: Chronic obstructive pulmonary disease (COPD) is a risk factor for atrial fibrillation (AF). The aim of this study was to investigate the impact of COPD on outcomes of catheter ablation in patients with AF in terms of recurrence and quality of life (QoL). Methods : In this prospective study, 550 consecutive patients with symptomatic, medication-refractory AF underwent first catheter ablation. Patients were classified into those with COPD (group 1, n = 54) and those without COPD (group 2, n = 496). Patients were followed up for atrial tachyarrhythmia (ATa) recurrence for at least 24 months. The Medical Outcomes Study SF-36 Health Survey was used to assess QoL at baseline and 24 months after ablation. Results : After a single ablation, 24 patients in group 1 (44.4%) and 142 in group 2 (28.6%) had ATa recurrence during a mean follow-up of 31.4 ± 4.8 months (P = 0.016). The second ablation was performed in 19 patients (35.2%) from group 1 and in 109 patients (22.0%) from group 2 (P = 0.029). Multivariate logistic analysis showed that nonparoxysmal AF (P = 0.013, OR = 1.767, 95% CI: 1.129-2.765) as well as the presence of COPD (P = 0.029, OR = 1.951, 95% CI: 1.070-3.557) was the independent predictor for higher ATa recurrence. Moreover, patients in group 1 had significantly lower baseline scores on all SF-36 Health Survey subscales. At 24-month follow-up, both mental component summary and physical component summary scores improved markedly in group 1 and 2. Conclusions : Although the presence of COPD predicted higher recurrence after single-catheter ablation in AF patients, significant improvements in QoL were observed in the postablation COPD population. (J Cardiovasc Electrophysiol, Vol. 24, pp. 148-154, February 2013) [ABSTRACT FROM AUTHOR]

Current challenge in spinal cord tissue engineering which is used in the spinal cord injury is to produce an implantable scaffold capable of bridging the nerve gaps which will produce results similar to autograft without requiring autologous donor tissue. Blending heparan sulfate proteoglycan (HSPG) with collagen resulted in increased hydrophilicity, high porosity (89%), improved mechanical properties and suitable pore sizes were fabricated by optical chemical crosslinking method. The biocompatibility of HSPG/collagen scaffold was assessed for culturing neural stem cells which assisted in directing the growth of regenerating axons in nerve tissue engineering and proliferation by performing MTS assay in vitro. The results of MTS assay and Scanning Electron Microscopy study confirmed the parallel and porous HSPG/collagen scaffold are suitable substrates for spinal cord tissue engineering. [ABSTRACT FROM AUTHOR]

Abstract: This paper presents a systematic method to establish the kinematics model for a tracked mobile manipulator on firm grounds, with consideration of the interactive motions between the tracks and the terrain, as well as those between the tracked vehicle and the onboard manipulator. Kinematics analysis is essential for real-time pose estimation and online autonomous navigation of tracked mobile manipulators. Furthermore, to improve the effectiveness of motion planning, and to simulate or control tracked mobile manipulators, a reliable kinematics model is required. However, kinematics modeling for a tracked mobile manipulator is complicated by the fact that there are infinite number of contact points between the tracks and the terrain, which makes slippage unavoidable. The track–terrain and vehicle–manipulator interactions make the problem even more complicated as the motion of the onboard manipulator and the centrifugal forces during moderate or high speed motion give rise to transfer of the load distribution, which will affect the longitudinal and lateral tractive forces and the resistance. Also, the motion of the mobile platform contributes to the inertial forces of the manipulator, and the track–terrain interactive forces help balance the gravity as well as the manipulation forces. The developed kinematics modeling approach is presented on the basis of a tracked mobile manipulator in our laboratory, but the forward kinematics analysis method, and the track–terrain and vehicle–manipulator interaction analysis algorithm are general, and can be used for any tracked mobile manipulators with little modification. This work lays a solid foundation for autonomous control, online slippage estimation, real-time traction optimization as well as tip-over prediction and prevention of tracked mobile manipulators. [Copyright &y& Elsevier]

Phytochemicals self-stabilized Pickering emulsion is expected to be a highly desirable oral self-delivery system. In this study, ursolic acid (UA), a representative pentacyclic triterpene, was reported for the first time that can be formed self-stabilized Pickering emulsion. That is, it is experimentally and theoretically proved that water-in-oil Pickering emulsion could be stabilized solely by UA. First, the morphology, wettability and interfacial properties of the UA particles were characterized. Then, the influence of variation with UA particle concentration (c) and water fraction (ϕ) on the droplet size and coalescence (and sedimentation) stability of UA stabilized emulsions were also studied. It was found that the formed emulsions performed excellent sediment stability except that under conditions where the UA particle concentration is low (c=1 wt%) or at low water fraction(ϕ=0.1). The viscoelastic properties of the emulsions could be improved with the increasing c or ϕ. Finally, The molecular dynamics simulation further verified that the UA particles are located at the oil-water interface and incompletely wrapped the water droplets to form a stable W/O Pickering emulsion. This work enriches the family of sustainable W/O Pickering stabilizers and provides a new strategy for the construction of a Carrier-Free Delivery System for pentacyclic triterpenes. [Display omitted] • The first finding of naturally occurring pentacyclic triterpene self-stabilized Pickering emulsion. • The influences of particle concentration and water volume fraction were investigated in detail. • MD simulations are used to verify further the feasibility of UA particles for stabilizing W/O Pickering emulsion. • This work enriches the family of sustainable W/O Pickering stabilizers. [ABSTRACT FROM AUTHOR]