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Reducing the ever-growing level of CO2 in the atmosphere is critical for the sustainable development of human society in the context of global warming. Integration of the capture and upgrading of CO2 is, therefore, highly desirable since each process step is costly, both energetically and economically. Here, we report a CO2 direct air capture (DAC) and fixation process that produces methane. Low concentrations of CO2 (∼400 ppm) in the air are captured by an aqueous solution of sodium hydroxide to form carbonate. The carbonate is subsequently hydrogenated to methane, which is easily separated from the reaction system, catalyzed by TiO2-supported Ru in the aqueous phase with a selectivity of 99.9% among gas-phase products. The concurrent regenerated hydroxide, in turn, increases the alkalinity of the aqueous solution for further CO2 capture, thereby enabling this one-of-its-kind continuous CO2 capture and methanation process. Engineering simulations demonstrate the energy feasibility of this CO2 DAC and methanation process, highlighting its promise for potential large-scale applications.

Introduction Wearable exoskeletons are emerging technologies for providing movement assistance and rehabilitation for people with motor disorders. In this study, we focus on the specific gait pathology dropfoot, which is common after a stroke. Dropfoot makes it difficult to achieve foot clearance during swing and heel contact at early stance and often necessitates compensatory movements. Methods We developed a soft ankle exoskeleton consisting of actuation and transmission systems to assist two degrees of freedom simultaneously: dorsiflexion and eversion, then performed several proof-of-concept experiments on non-disabled persons. The actuation system consists of two motors worn on a waist belt. The transmission system provides assistive force to the medial and lateral sides of the forefoot via Bowden cables. The coupling design enables variable assistance of dorsiflexion and inversion at the same time, and a force-free controller is proposed to compensate for device resistance. We first evaluated the performance of the exoskeleton in three seated movement tests: assisting dorsiflexion and eversion, controlling plantarflexion, and compensating for device resistance, then during walking tests. In all proof-of-concept experiments, dropfoot tendency was simulated by fastening a weight to the shoe over the lateral forefoot. Results In the first two seated tests, errors between the target and the achieved ankle joint angles in two planes were low; errors of <1.5 degrees were achieved in assisting dorsiflexion and/or controlling plantarflexion and of <1.4 degrees in assisting ankle eversion. The force-free controller in test three significantly compensated for the device resistance during ankle joint plantarflexion. In the gait tests, the exoskeleton was able to normalize ankle joint and foot segment kinematics, specifically foot inclination angle and ankle inversion angle at initial contact and ankle angle and clearance height during swing. Discussion Our findings, QC 20240912

Integrating mobile eye-tracking and motion capture emerges as a promising approach in studying visual-motor coordination, due to its capability of expressing gaze data within the same laboratory-centered coordinate system as body movement data. In this paper, we proposed an integrated eye-tracking and motion capture system, which can record and analyze temporally and spatially synchronized gaze and motion data during dynamic movement. The accuracy of gaze measurement were evaluated on five participants while they were instructed to view fixed vision targets at different distances while standing still or walking towards the targets. Similar accuracy could be achieved in both static and dynamic conditions. To demonstrate the usability of the integrated system, several walking tasks were performed in three different pathways. Results revealed that participants tended to focus their gaze on the upcoming path, especially on the downward path, possibly for better navigation and planning. In a more complex pathway, coupled with more gaze time on the pathway, participants were also found having the longest step time and shortest step length, which led to the lowest walking speed. It was believed that the integration of eye-tracking and motion capture is a feasible and promising methodology quantifying visual-motor coordination in locomotion., Part of proceedings ISBN 979-8-3503-4275-8QC 20240109

Wearable robotics and exoskeletons have been explored for their efficacy in physical rehabilitation and for assistance in daily activities for people with motor disorders. The overall objective of this thesis is to design a powered soft exoskeleton for people with dropfoot and excessive inversion, commonly after a stroke, and to optimize the control parameters for each individual while considering different dimensions. This compilation thesis is based on two papers that focus on the design and verification of the ankle joint exoskeleton prototype, and control parameters optimization using human-in-the-loop optimization, respectively. In the first paper, we presented the design of the powered soft ankle exoskeleton, mainly consisting of the actuation system, Bowden cables, and textile components, to assist two degrees of freedom (DoF), dorsiflexion and eversion, simultaneously.A proof-of-concept study was performed to verify the functionality of the exoskeleton in two aspects: assisting/controlling two DoFs simultaneously and compensating for the resistance during ankle plantarflexion. Our results suggested that two-DoF assistance can be delivered with the structure, and the proposed force-free controller can counteract the inherent resistance in the system. In the second paper, a multi-objective-based human-in-the-loop optimization method was proposed, aiming at optimizing gait quality in different aspects simultaneously.In this case study, the multi-objective optimization method, Non-dominated Sorting Genetic Algorithm II, was implemented in the human-in-the-loop optimization. Four generations, comprising ten sets of control parameters in each generation, were tested on one non-disabled subject wearing the exoskeleton described in paper I. The results indicated that this novel method can identify the control laws that optimize both gait quality metrics. In the set of solutions, control laws with different focuses can be selected for different purposes or individual, Bärbara robotar och exoskelett har utforskats för deras effektivitet inom fysisk rehabilitering och som stöd i dagliga aktiviteter för personer med motoriska störningar. Det övergripande målet med denna avhandling är att designa en kraftdriven mjuk exoskelett för personer med fallfot och överdriven inversion, vanligt efter en stroke, och att optimera kontrollparametrarna för varje individ med hänsyn till olika dimensioner. Denna sammanställda avhandling bygger på två artiklar som fokuserar på design och verifiering av prototypen för fotledsexoskelett samt optimering av kontrollparametrar med mänsklig medverkan. I den första artikeln presenterade vi designen av det kraftdrivna mjuka fotledsexoskelettet, som huvudsakligen består av aktiveringssystem, Bowden-kablar och textilkomponenter, för att assistera i två grader av frihet (DoF), dorsiflexion och eversion, samtidigt. En konceptbevisstudie genomfördes för att verifiera funktionen hos exoskelettet avseende två aspekter: assistera/styra två DoFs samtidigt och kompensera för motståndet under plantarflektion i fotleden. Våra resultat antydde att två-DoF-assistans kan levereras med strukturen och att den föreslagna kraftfria styrenheten kan motverka det inneboende motståndet i systemet. I den andra artikeln föreslogs en mänsklig medverkande optimeringsmetod baserad på flera mål, med syfte att optimera gångkvaliteten i olika aspekter samtidigt. I denna fallstudie implementerades den flerobjektiva optimeringsmetoden Non-dominated Sorting Genetic Algorithm II i den mänskliga medverkansoptimeringen. Fyra generationer, med tio uppsättningar av kontrollparametrar i varje generation, testades på en icke-funktionshindrad försöksperson som bar det exoskelett som beskrivs i den första artikeln. Resultaten indikerade att denna nya metod kan identifiera styrregler som optimerar både gångkvalitetsmått. I uppsättningen lösningar kan styrregler med olika fokus väljas för olika ändamål eller individuella användningsområden., QC 231115

Research interest in exoskeleton assistance strategies that incorporate the user's torque capacity is rapidly growing, yet uncertainty in predicted torque capacity can significantly impact the user-exoskeleton interface safety. In this paper, we estimated knee flexion/extension torques by using a neuromusculoskeletal (NMS) solver-informed Gaussian process (NMS-GP) model with muscle electromyography signals and joint kinematics as model inputs. The NMS-GP model combined the NMS and GP models by integrating valuable features from an NMS solver into a GP model. The NMSGP model was used to predict knee joint torque in daily activities with uncertainty quantification. The activities included slow walking, self-selected speed walking, fast walking, sit-to-stand, and stand-to-sit. Model performance, defined as low prediction error between the model's predicted torque and measured torques from inverse dynamics computations, of both the NMS-GP and NMS models was analyzed. We found that prediction error was significantly lower in NMS-GP models than in NMS models. We observed relatively high uncertainties in the predicted knee torque at the beginning of each movement, particularly in self-selected speed walking. High uncertainties were also found during terminal stance and swing in self-selected speed walking. Compared to other torque prediction methods, the proposed NMS-GP model not only provides an accurate joint torque prediction but also a measure of the uncertainty. Our study showed that the NMS-GP model has a large potential in control strategy design for rehabilitation exoskeletons and to enhance the overall user experience., Part of ISBN 9798350300178QC 20231010

Introduction: Research interest in exoskeleton assistance strategies that incorporate the user's torque capacity is growing rapidly. However, the predicted torque capacity from users often includes uncertainty from various sources, which can have a significant impact on the safety of the exoskeleton-user interface. Methods: To address this challenge, this paper proposes an adaptive control framework for a knee exoskeleton that uses muscle electromyography (EMG) signals and joint kinematics. The framework predicted the user's knee flexion/extension torque with confidence bounds to quantify the uncertainty based on a neuromusculoskeletal (NMS) solver-informed Bayesian Neural Network (NMS-BNN). The predicted torque, with a specified confidence level, controlled the assistive torque provided by the exoskeleton through a TCP/IP stream. The performance of the NMS-BNN model was also compared to that of the Gaussian process (NMS-GP) model. Results: Our findings showed that both the NMS-BNN and NMS-GP models accurately predicted knee joint torque with low error, surpassing traditional NMS models. High uncertainties were observed at the beginning of each movement, and at terminal stance and terminal swing in self-selected speed walking in both NMS-BNN and NMS-GP models. The knee exoskeleton provided the desired assistive torque with a low error, although lower torque was observed during terminal stance of fast walking compared to self-selected walking speed. Discussion: The framework developed in this study was able to predict knee flexion/extension torque with quantifiable uncertainty and to provide adaptive assistive torque to the user. This holds significant potential for the development of exoskeletons that provide assistance as needed, with a focus on the safety of the exoskeleton-user interface., QC 20231006

Wearable robotics and exoskeletons have been explored for their efficacy in physical rehabilitation and for assistance in daily activities for people with motor disorders. The overall objective of this thesis is to design a powered soft exoskeleton for people with dropfoot and excessive inversion, commonly after a stroke, and to optimize the control parameters for each individual while considering different dimensions. This compilation thesis is based on two papers that focus on the design and verification of the ankle joint exoskeleton prototype, and control parameters optimization using human-in-the-loop optimization, respectively. In the first paper, we presented the design of the powered soft ankle exoskeleton, mainly consisting of the actuation system, Bowden cables, and textile components, to assist two degrees of freedom (DoF), dorsiflexion and eversion, simultaneously.A proof-of-concept study was performed to verify the functionality of the exoskeleton in two aspects: assisting/controlling two DoFs simultaneously and compensating for the resistance during ankle plantarflexion. Our results suggested that two-DoF assistance can be delivered with the structure, and the proposed force-free controller can counteract the inherent resistance in the system. In the second paper, a multi-objective-based human-in-the-loop optimization method was proposed, aiming at optimizing gait quality in different aspects simultaneously.In this case study, the multi-objective optimization method, Non-dominated Sorting Genetic Algorithm II, was implemented in the human-in-the-loop optimization. Four generations, comprising ten sets of control parameters in each generation, were tested on one non-disabled subject wearing the exoskeleton described in paper I. The results indicated that this novel method can identify the control laws that optimize both gait quality metrics. In the set of solutions, control laws with different focuses can be selected for different purposes or individual, Bärbara robotar och exoskelett har utforskats för deras effektivitet inom fysisk rehabilitering och som stöd i dagliga aktiviteter för personer med motoriska störningar. Det övergripande målet med denna avhandling är att designa en kraftdriven mjuk exoskelett för personer med fallfot och överdriven inversion, vanligt efter en stroke, och att optimera kontrollparametrarna för varje individ med hänsyn till olika dimensioner. Denna sammanställda avhandling bygger på två artiklar som fokuserar på design och verifiering av prototypen för fotledsexoskelett samt optimering av kontrollparametrar med mänsklig medverkan. I den första artikeln presenterade vi designen av det kraftdrivna mjuka fotledsexoskelettet, som huvudsakligen består av aktiveringssystem, Bowden-kablar och textilkomponenter, för att assistera i två grader av frihet (DoF), dorsiflexion och eversion, samtidigt. En konceptbevisstudie genomfördes för att verifiera funktionen hos exoskelettet avseende två aspekter: assistera/styra två DoFs samtidigt och kompensera för motståndet under plantarflektion i fotleden. Våra resultat antydde att två-DoF-assistans kan levereras med strukturen och att den föreslagna kraftfria styrenheten kan motverka det inneboende motståndet i systemet. I den andra artikeln föreslogs en mänsklig medverkande optimeringsmetod baserad på flera mål, med syfte att optimera gångkvaliteten i olika aspekter samtidigt. I denna fallstudie implementerades den flerobjektiva optimeringsmetoden Non-dominated Sorting Genetic Algorithm II i den mänskliga medverkansoptimeringen. Fyra generationer, med tio uppsättningar av kontrollparametrar i varje generation, testades på en icke-funktionshindrad försöksperson som bar det exoskelett som beskrivs i den första artikeln. Resultaten indikerade att denna nya metod kan identifiera styrregler som optimerar både gångkvalitetsmått. I uppsättningen lösningar kan styrregler med olika fokus väljas för olika ändamål eller individuella användningsområden., QC 231115

Wearable robotics and exoskeletons have been explored for their efficacy in physical rehabilitation and for assistance in daily activities for people with motor disorders. The overall objective of this thesis is to design a powered soft exoskeleton for people with dropfoot and excessive inversion, commonly after a stroke, and to optimize the control parameters for each individual while considering different dimensions. This compilation thesis is based on two papers that focus on the design and verification of the ankle joint exoskeleton prototype, and control parameters optimization using human-in-the-loop optimization, respectively. In the first paper, we presented the design of the powered soft ankle exoskeleton, mainly consisting of the actuation system, Bowden cables, and textile components, to assist two degrees of freedom (DoF), dorsiflexion and eversion, simultaneously.A proof-of-concept study was performed to verify the functionality of the exoskeleton in two aspects: assisting/controlling two DoFs simultaneously and compensating for the resistance during ankle plantarflexion. Our results suggested that two-DoF assistance can be delivered with the structure, and the proposed force-free controller can counteract the inherent resistance in the system. In the second paper, a multi-objective-based human-in-the-loop optimization method was proposed, aiming at optimizing gait quality in different aspects simultaneously.In this case study, the multi-objective optimization method, Non-dominated Sorting Genetic Algorithm II, was implemented in the human-in-the-loop optimization. Four generations, comprising ten sets of control parameters in each generation, were tested on one non-disabled subject wearing the exoskeleton described in paper I. The results indicated that this novel method can identify the control laws that optimize both gait quality metrics. In the set of solutions, control laws with different focuses can be selected for different purposes or individual, Bärbara robotar och exoskelett har utforskats för deras effektivitet inom fysisk rehabilitering och som stöd i dagliga aktiviteter för personer med motoriska störningar. Det övergripande målet med denna avhandling är att designa en kraftdriven mjuk exoskelett för personer med fallfot och överdriven inversion, vanligt efter en stroke, och att optimera kontrollparametrarna för varje individ med hänsyn till olika dimensioner. Denna sammanställda avhandling bygger på två artiklar som fokuserar på design och verifiering av prototypen för fotledsexoskelett samt optimering av kontrollparametrar med mänsklig medverkan. I den första artikeln presenterade vi designen av det kraftdrivna mjuka fotledsexoskelettet, som huvudsakligen består av aktiveringssystem, Bowden-kablar och textilkomponenter, för att assistera i två grader av frihet (DoF), dorsiflexion och eversion, samtidigt. En konceptbevisstudie genomfördes för att verifiera funktionen hos exoskelettet avseende två aspekter: assistera/styra två DoFs samtidigt och kompensera för motståndet under plantarflektion i fotleden. Våra resultat antydde att två-DoF-assistans kan levereras med strukturen och att den föreslagna kraftfria styrenheten kan motverka det inneboende motståndet i systemet. I den andra artikeln föreslogs en mänsklig medverkande optimeringsmetod baserad på flera mål, med syfte att optimera gångkvaliteten i olika aspekter samtidigt. I denna fallstudie implementerades den flerobjektiva optimeringsmetoden Non-dominated Sorting Genetic Algorithm II i den mänskliga medverkansoptimeringen. Fyra generationer, med tio uppsättningar av kontrollparametrar i varje generation, testades på en icke-funktionshindrad försöksperson som bar det exoskelett som beskrivs i den första artikeln. Resultaten indikerade att denna nya metod kan identifiera styrregler som optimerar både gångkvalitetsmått. I uppsättningen lösningar kan styrregler med olika fokus väljas för olika ändamål eller individuella användningsområden., QC 231115

Wearable robotics and exoskeletons have been explored for their efficacy in physical rehabilitation and for assistance in daily activities for people with motor disorders. The overall objective of this thesis is to design a powered soft exoskeleton for people with dropfoot and excessive inversion, commonly after a stroke, and to optimize the control parameters for each individual while considering different dimensions. This compilation thesis is based on two papers that focus on the design and verification of the ankle joint exoskeleton prototype, and control parameters optimization using human-in-the-loop optimization, respectively. In the first paper, we presented the design of the powered soft ankle exoskeleton, mainly consisting of the actuation system, Bowden cables, and textile components, to assist two degrees of freedom (DoF), dorsiflexion and eversion, simultaneously.A proof-of-concept study was performed to verify the functionality of the exoskeleton in two aspects: assisting/controlling two DoFs simultaneously and compensating for the resistance during ankle plantarflexion. Our results suggested that two-DoF assistance can be delivered with the structure, and the proposed force-free controller can counteract the inherent resistance in the system. In the second paper, a multi-objective-based human-in-the-loop optimization method was proposed, aiming at optimizing gait quality in different aspects simultaneously.In this case study, the multi-objective optimization method, Non-dominated Sorting Genetic Algorithm II, was implemented in the human-in-the-loop optimization. Four generations, comprising ten sets of control parameters in each generation, were tested on one non-disabled subject wearing the exoskeleton described in paper I. The results indicated that this novel method can identify the control laws that optimize both gait quality metrics. In the set of solutions, control laws with different focuses can be selected for different purposes or individual, Bärbara robotar och exoskelett har utforskats för deras effektivitet inom fysisk rehabilitering och som stöd i dagliga aktiviteter för personer med motoriska störningar. Det övergripande målet med denna avhandling är att designa en kraftdriven mjuk exoskelett för personer med fallfot och överdriven inversion, vanligt efter en stroke, och att optimera kontrollparametrarna för varje individ med hänsyn till olika dimensioner. Denna sammanställda avhandling bygger på två artiklar som fokuserar på design och verifiering av prototypen för fotledsexoskelett samt optimering av kontrollparametrar med mänsklig medverkan. I den första artikeln presenterade vi designen av det kraftdrivna mjuka fotledsexoskelettet, som huvudsakligen består av aktiveringssystem, Bowden-kablar och textilkomponenter, för att assistera i två grader av frihet (DoF), dorsiflexion och eversion, samtidigt. En konceptbevisstudie genomfördes för att verifiera funktionen hos exoskelettet avseende två aspekter: assistera/styra två DoFs samtidigt och kompensera för motståndet under plantarflektion i fotleden. Våra resultat antydde att två-DoF-assistans kan levereras med strukturen och att den föreslagna kraftfria styrenheten kan motverka det inneboende motståndet i systemet. I den andra artikeln föreslogs en mänsklig medverkande optimeringsmetod baserad på flera mål, med syfte att optimera gångkvaliteten i olika aspekter samtidigt. I denna fallstudie implementerades den flerobjektiva optimeringsmetoden Non-dominated Sorting Genetic Algorithm II i den mänskliga medverkansoptimeringen. Fyra generationer, med tio uppsättningar av kontrollparametrar i varje generation, testades på en icke-funktionshindrad försöksperson som bar det exoskelett som beskrivs i den första artikeln. Resultaten indikerade att denna nya metod kan identifiera styrregler som optimerar både gångkvalitetsmått. I uppsättningen lösningar kan styrregler med olika fokus väljas för olika ändamål eller individuella användningsområden., QC 231115

Wearable robotics and exoskeletons have been explored for their efficacy in physical rehabilitation and for assistance in daily activities for people with motor disorders. The overall objective of this thesis is to design a powered soft exoskeleton for people with dropfoot and excessive inversion, commonly after a stroke, and to optimize the control parameters for each individual while considering different dimensions. This compilation thesis is based on two papers that focus on the design and verification of the ankle joint exoskeleton prototype, and control parameters optimization using human-in-the-loop optimization, respectively. In the first paper, we presented the design of the powered soft ankle exoskeleton, mainly consisting of the actuation system, Bowden cables, and textile components, to assist two degrees of freedom (DoF), dorsiflexion and eversion, simultaneously.A proof-of-concept study was performed to verify the functionality of the exoskeleton in two aspects: assisting/controlling two DoFs simultaneously and compensating for the resistance during ankle plantarflexion. Our results suggested that two-DoF assistance can be delivered with the structure, and the proposed force-free controller can counteract the inherent resistance in the system. In the second paper, a multi-objective-based human-in-the-loop optimization method was proposed, aiming at optimizing gait quality in different aspects simultaneously.In this case study, the multi-objective optimization method, Non-dominated Sorting Genetic Algorithm II, was implemented in the human-in-the-loop optimization. Four generations, comprising ten sets of control parameters in each generation, were tested on one non-disabled subject wearing the exoskeleton described in paper I. The results indicated that this novel method can identify the control laws that optimize both gait quality metrics. In the set of solutions, control laws with different focuses can be selected for different purposes or individual, Bärbara robotar och exoskelett har utforskats för deras effektivitet inom fysisk rehabilitering och som stöd i dagliga aktiviteter för personer med motoriska störningar. Det övergripande målet med denna avhandling är att designa en kraftdriven mjuk exoskelett för personer med fallfot och överdriven inversion, vanligt efter en stroke, och att optimera kontrollparametrarna för varje individ med hänsyn till olika dimensioner. Denna sammanställda avhandling bygger på två artiklar som fokuserar på design och verifiering av prototypen för fotledsexoskelett samt optimering av kontrollparametrar med mänsklig medverkan. I den första artikeln presenterade vi designen av det kraftdrivna mjuka fotledsexoskelettet, som huvudsakligen består av aktiveringssystem, Bowden-kablar och textilkomponenter, för att assistera i två grader av frihet (DoF), dorsiflexion och eversion, samtidigt. En konceptbevisstudie genomfördes för att verifiera funktionen hos exoskelettet avseende två aspekter: assistera/styra två DoFs samtidigt och kompensera för motståndet under plantarflektion i fotleden. Våra resultat antydde att två-DoF-assistans kan levereras med strukturen och att den föreslagna kraftfria styrenheten kan motverka det inneboende motståndet i systemet. I den andra artikeln föreslogs en mänsklig medverkande optimeringsmetod baserad på flera mål, med syfte att optimera gångkvaliteten i olika aspekter samtidigt. I denna fallstudie implementerades den flerobjektiva optimeringsmetoden Non-dominated Sorting Genetic Algorithm II i den mänskliga medverkansoptimeringen. Fyra generationer, med tio uppsättningar av kontrollparametrar i varje generation, testades på en icke-funktionshindrad försöksperson som bar det exoskelett som beskrivs i den första artikeln. Resultaten indikerade att denna nya metod kan identifiera styrregler som optimerar både gångkvalitetsmått. I uppsättningen lösningar kan styrregler med olika fokus väljas för olika ändamål eller individuella användningsområden., QC 231115

We leverage different context windows when predicting the emotion of different utterances. New modules are included to realize variable-length context: 1) two speaker-aware units, which explicitly model inner- and inter-speaker dependencies to form distilled conversational context, and 2) a top-k normalization layer, which determines the most proper context windows from the conversational context to predict emotion. Experiments and ablation studies show that our approach outperforms several strong baselines on three public datasets.

Self-supervised representation learning~(SSRL) has advanced considerably by exploiting the transformation invariance assumption under artificially designed data augmentations. While augmentation-based SSRL algorithms push the boundaries of performance in computer vision and natural language processing, they are often not directly applicable to other data modalities, and can conflict with application-specific data augmentation constraints. This paper presents an SSRL approach that can be applied to any data modality and network architecture because it does not rely on augmentations or masking. Specifically, we show that high-quality data representations can be learned by reconstructing random data projections. We evaluate the proposed approach on a wide range of representation learning tasks that span diverse modalities and real-world applications. We show that it outperforms multiple state-of-the-art SSRL baselines. Due to its wide applicability and strong empirical results, we argue that learning from randomness is a fruitful research direction worthy of attention and further study., Comment: Published as a conference paper of ICLR 2024. https://openreview.net/pdf?id=EpYnZpDpsQ

A greeting is a common polite behaviour that also helps to build a relationship. Knowing the difference between Chinese and western greetings will help communicate better with foreigners in the future, and help Chinese and western cultures communicate better with each other. This paper looks at the differences in greetings between Chinese and western cultures and societies and explains why these differences exist based on economy, culture, and society. Furthermore, this paper also suggests that to achieve a better expression result, it is important to pay attention to these differences in communication.

A greeting is a common polite behaviour that also helps to build a relationship. Knowing the difference between Chinese and western greetings will help communicate better with foreigners in the future, and help Chinese and western cultures communicate better with each other. This paper looks at the differences in greetings between Chinese and western cultures and societies and explains why these differences exist based on economy, culture, and society. Furthermore, this paper also suggests that to achieve a better expression result, it is important to pay attention to these differences in communication.

IntroductionPhysical activity can attenuate cancer-related declines in physical functioning, improve emotional well-being, and prolong survival among older (≥65 years) breast cancer survivors. However, factors associated with physical activity among older breast cancer survivors are not well-understood.Materials and methodsParticipants were enrolled in the Women's Health Initiative (WHI) Life and Longevity After Cancer (LILAC) study. Descriptive statistics, multiple linear regression, and relative risk [RR] regression were used to assess the association of demographic, clinical, physical and psychosocial variables with the total duration of and participation in physical activity among postmenopausal breast cancer survivors. Age-specific correlates (65-74 years vs. 75-84 years vs. ≥85 years) of physical activity were also examined.ResultsThe majority of participants (n = 3710, mean age = 78.8 ± 5.9) were white (90.7%) and had in situ/localized breast cancer (78.9%). Women who had higher education (RR = 1.47 for graduate/professional school versus high school or less, 95% CI: 1.32, 1.63), higher self-rated health (RR = 1.04 for 10 point increase, 95% CI:1.02, 1.07), higher physical functioning (RR = 1.03 for 5 point increase, 95% CI: 1.02, 1.04), and higher social support (RR = 1.41 for social support all of the time versus none of the time, 95% CI: 1.01, 1.96), were more likely to engage in any physical activity. Similar results were observed for duration of physical activity. Among women aged <75, radiation therapy, but not chemotherapy, was associated with longer duration of total physical activity (adjusted difference = 19.7 min/week, 95% CI: 6.1, 33.3), but was not associated with duration among older women. The association between pain and duration of moderate/strenuous activity also differed with age: among women aged <75, those with moderate pain aver

PurposeLifestyle factors such as smoking, alcohol, body weight, physical activity, and diet quality have been associated with the risk of pancreatic cancer. However, studies of their combined association in women are limited.MethodsData on smoking habits, alcohol intake, diet composition, recreational physical activity, body weight, and waist circumference, obtained at recruitment for 136,945 postmenopausal women (aged 50-79 years) participating in the Women's Health Initiative study, were categorized separately, with higher scores for each variable assigned to the categories representing healthier behaviors. The combined healthy lifestyle index (HLI) score, created by summing the scores for each risk factor, was grouped into quartiles. We used multivariable-adjusted Cox regression to estimate hazard ratios (HR) and 95% confidence intervals (CI) for pancreatic cancer risk in association with the HLI.ResultsOver an average follow-up period of approximately 16.0 years, 1,119 incident cases of pancreatic cancer were ascertained. Compared to women in the lowest HLI quartile, those in the upper quartiles (qt) had a reduced risk of pancreatic cancer (multivariable-adjusted HRqt3rd 0.83, 95% CI 0.74-0.99; and HRqt4th 0.74, 95% CI 0.62-0.88, respectively, p trend = 0.001). Use of waist circumference instead of BMI in the HLI score yielded similar results. Among women who were either non-diabetic or non-smokers, high HLI was also associated with reduced risk (HRqt4th 0.78, 95% CI 0.65-0.85 and HRqt4th 0.80, 95% CI 0.66-0.97, respectively). Stratification by BMI categories (18.5- < 25.0, 25.0- < 30.0 and > 30.0 kg/m2) showed similar results in all groups.ConclusionsOur findings suggest that in postmenopausal women, a healthy lifestyle is associated with reduced risk of pancreatic cancer.

Photosynthesis with the chloroplast works efficiently because of the envelope structure that serves to carry enzymes and to simultaneously maintain the spatial separation of photosynthesis and cellular respiration. Inspired by the spatially separated architecture, a chloroplast-like structured photocatalyst (PdS@CdS@MoS2), in which the PdS and MoS2 function as enzymes in the chloroplast and CdS shell functions as the chloroplast envelope, was developed to improve the photocatalytic H2 evolution. In this unique nanoscale bionic structure, the poriferous CdS shell enhances light absorption, generates photoinduced carriers, and separates oxidation and reduction reactions. Meanwhile, PdS and MoS2 dual cocatalysts enhance the charge separation efficiency through forming a built-in electric field with CdS. We demonstrate that the separation efficiency of carriers, carrier lifetime, and the yield of H2 are both higher than that of CdS nanoparticles, evidencing the feasibility of the chloroplast-like structure in enhancing the photocatalyst activity. This work emphasizes the synergism of the three key processes of the photocatalytic reaction by simulating the chloroplast structure and provides a general synthesis strategy, the synthesis of novel structured for photocatalysts for diverse applications in the energy field. © 2021 Zhengzhou University

A greeting is a common polite behaviour that also helps to build a relationship. Knowing the difference between Chinese and western greetings will help communicate better with foreigners in the future, and help Chinese and western cultures communicate better with each other. This paper looks at the differences in greetings between Chinese and western cultures and societies and explains why these differences exist based on economy, culture, and society. Furthermore, this paper also suggests that to achieve a better expression result, it is important to pay attention to these differences in communication.

A greeting is a common polite behaviour that also helps to build a relationship. Knowing the difference between Chinese and western greetings will help communicate better with foreigners in the future, and help Chinese and western cultures communicate better with each other. This paper looks at the differences in greetings between Chinese and western cultures and societies and explains why these differences exist based on economy, culture, and society. Furthermore, this paper also suggests that to achieve a better expression result, it is important to pay attention to these differences in communication.

A greeting is a common polite behaviour that also helps to build a relationship. Knowing the difference between Chinese and western greetings will help communicate better with foreigners in the future, and help Chinese and western cultures communicate better with each other. This paper looks at the differences in greetings between Chinese and western cultures and societies and explains why these differences exist based on economy, culture, and society. Furthermore, this paper also suggests that to achieve a better expression result, it is important to pay attention to these differences in communication.

A greeting is a common polite behaviour that also helps to build a relationship. Knowing the difference between Chinese and western greetings will help communicate better with foreigners in the future, and help Chinese and western cultures communicate better with each other. This paper looks at the differences in greetings between Chinese and western cultures and societies and explains why these differences exist based on economy, culture, and society. Furthermore, this paper also suggests that to achieve a better expression result, it is important to pay attention to these differences in communication.

A greeting is a common polite behaviour that also helps to build a relationship. Knowing the difference between Chinese and western greetings will help communicate better with foreigners in the future, and help Chinese and western cultures communicate better with each other. This paper looks at the differences in greetings between Chinese and western cultures and societies and explains why these differences exist based on economy, culture, and society. Furthermore, this paper also suggests that to achieve a better expression result, it is important to pay attention to these differences in communication.

A greeting is a common polite behaviour that also helps to build a relationship. Knowing the difference between Chinese and western greetings will help communicate better with foreigners in the future, and help Chinese and western cultures communicate better with each other. This paper looks at the differences in greetings between Chinese and western cultures and societies and explains why these differences exist based on economy, culture, and society. Furthermore, this paper also suggests that to achieve a better expression result, it is important to pay attention to these differences in communication.

A greeting is a common polite behaviour that also helps to build a relationship. Knowing the difference between Chinese and western greetings will help communicate better with foreigners in the future, and help Chinese and western cultures communicate better with each other. This paper looks at the differences in greetings between Chinese and western cultures and societies and explains why these differences exist based on economy, culture, and society. Furthermore, this paper also suggests that to achieve a better expression result, it is important to pay attention to these differences in communication.

Photosynthesis with the chloroplast works efficiently because of the envelope structure that serves to carry enzymes and to simultaneously maintain the spatial separation of photosynthesis and cellular respiration. Inspired by the spatially separated architecture, a chloroplast-like structured photocatalyst (PdS@CdS@MoS2), in which the PdS and MoS2 function as enzymes in the chloroplast and CdS shell functions as the chloroplast envelope, was developed to improve the photocatalytic H2 evolution. In this unique nanoscale bionic structure, the poriferous CdS shell enhances light absorption, generates photoinduced carriers, and separates oxidation and reduction reactions. Meanwhile, PdS and MoS2 dual cocatalysts enhance the charge separation efficiency through forming a built-in electric field with CdS. We demonstrate that the separation efficiency of carriers, carrier lifetime, and the yield of H2 are both higher than that of CdS nanoparticles, evidencing the feasibility of the chloroplast-like structure in enhancing the photocatalyst activity. This work emphasizes the synergism of the three key processes of the photocatalytic reaction by simulating the chloroplast structure and provides a general synthesis strategy, the synthesis of novel structured for photocatalysts for diverse applications in the energy field. © 2021 Zhengzhou University

Photosynthesis with the chloroplast works efficiently because of the envelope structure that serves to carry enzymes and to simultaneously maintain the spatial separation of photosynthesis and cellular respiration. Inspired by the spatially separated architecture, a chloroplast-like structured photocatalyst (PdS@CdS@MoS2), in which the PdS and MoS2 function as enzymes in the chloroplast and CdS shell functions as the chloroplast envelope, was developed to improve the photocatalytic H2 evolution. In this unique nanoscale bionic structure, the poriferous CdS shell enhances light absorption, generates photoinduced carriers, and separates oxidation and reduction reactions. Meanwhile, PdS and MoS2 dual cocatalysts enhance the charge separation efficiency through forming a built-in electric field with CdS. We demonstrate that the separation efficiency of carriers, carrier lifetime, and the yield of H2 are both higher than that of CdS nanoparticles, evidencing the feasibility of the chloroplast-like structure in enhancing the photocatalyst activity. This work emphasizes the synergism of the three key processes of the photocatalytic reaction by simulating the chloroplast structure and provides a general synthesis strategy, the synthesis of novel structured for photocatalysts for diverse applications in the energy field. © 2021 Zhengzhou University

Silicon nitride ceramic bearings are widely used for their excellent performance. However, due to their special manufacturing method, cracks will occur on ceramic ball surface, and this initial surface crack will propagate under the action of cyclic stress, which will lead to material spalling. This will greatly limit its service life in practical applications, especially under heavy load at high speed. Therefore, it is necessary to study the surface crack propagation of silicon nitride ceramic bearings. In this paper, the effect of initial crack angle and contact load on crack growth is analysed by the finite element method (FEM). A three-dimensional finite element model of a silicon nitride bearing ball containing an initial crack is created by the FEM. The cracks are initially classified based on the angle between the crack and the bearing ball surface, and the location of the most dangerous load for each type of crack is known by theoretical analysis. The stress intensity factors (SIFs) are calculated for the crack front to investigate the effect of load position on crack growth. Subsequently, the SIFs are calculated for each type of crack angle subdivided again to investigate the effect of crack angle on crack propagation.

Silicon nitride ceramic bearings are widely used for their excellent performance. However, due to their special manufacturing method, cracks will occur on ceramic ball surface, and this initial surface crack will propagate under the action of cyclic stress, which will lead to material spalling. This will greatly limit its service life in practical applications, especially under heavy load at high speed. Therefore, it is necessary to study the surface crack propagation of silicon nitride ceramic bearings. In this paper, the effect of initial crack angle and contact load on crack growth is analysed by the finite element method (FEM). A three-dimensional finite element model of a silicon nitride bearing ball containing an initial crack is created by the FEM. The cracks are initially classified based on the angle between the crack and the bearing ball surface, and the location of the most dangerous load for each type of crack is known by theoretical analysis. The stress intensity factors (SIFs) are calculated for the crack front to investigate the effect of load position on crack growth. Subsequently, the SIFs are calculated for each type of crack angle subdivided again to investigate the effect of crack angle on crack propagation.

Recommender systems have been introduced to help consumers navigate large sets of alternatives. They usually lead to more sales, which may increase consumer surplus and firm profit. In this paper, we ask whether the firms’ choice of recommender system might hurt consumers. We use data from a large-scale field experiment in video-on-demand to measure the price elasticity of demand for movies placed in salient and non-salient slots on the TV screen. During this experiment, the firm randomized the prices and slots in which movies were recommended to consumers. This setting readily allows for identifying the effects of price and slot on demand, and thus computes consumer surplus. We find that consumers are less price-elastic toward movies placed in salient slots. Using the outcomes of this experiment, we simulate how consumer surplus and welfare change when the firm implements several types of recommender systems, namely one that maximizes profit. We show that this system hurts consumer surplus and welfare relative to a system that maximizes welfare. We also show that, in our setting, the system that maximizes profit does not generate less consumer surplus than several recommender systems frequently used in practice. Yet, the amount of extra rent the firm can extract from strategically placing movies in salient slots is still a function of the popularity and quality of movies used to do so. Ultimately, our results question whether recommender systems embed mechanisms that extract excessive surplus from consumers, which may call for better scrutiny.

Machine learning (ML) has been widely used for efficient resource allocation (RA) in wireless networks. Although superb performance is achieved on small and simple networks, most existing ML-based approaches are confronted with difficulties when heterogeneity occurs and network size expands. In this paper, specifically focusing on power control/beamforming (PC/BF) in heterogeneous device-to-device (D2D) networks, we propose a novel unsupervised learning-based framework named heterogeneous interference graph neural network (HIGNN) to handle these challenges. First, we characterize diversified link features and interference relations with heterogeneous graphs. Then, HIGNN is proposed to empower each link to obtain its individual transmission scheme after limited information exchange with neighboring links. It is noteworthy that HIGNN is scalable to wireless networks of growing sizes with robust performance after trained on small-sized networks. Numerical results show that compared with state-of-the-art benchmarks, HIGNN achieves much higher execution efficiency while providing strong performance., Comment: 6 pages, 6 figures, accepted by IEEE GLOBECOM 2021. Copyright may be transferred without notice, after which this version may no longer be accessible

Multiple-input multiple-output orthogonal frequency-division multiplexing (MIMO-OFDM) is a key technology component in the evolution towards cognitive radio (CR) in next-generation communication in which the accuracy of timing and frequency synchronization significantly impacts the overall system performance. In this paper, we propose a novel scheme leveraging extreme learning machine (ELM) to achieve high-precision synchronization. Specifically, exploiting the preamble signals with synchronization offsets, two ELMs are incorporated into a traditional MIMO-OFDM system to estimate both the residual symbol timing offset (RSTO) and the residual carrier frequency offset (RCFO). The simulation results show that the performance of the proposed ELM-based synchronization scheme is superior to the traditional method under both additive white Gaussian noise (AWGN) and frequency selective fading channels. Furthermore, comparing with the existing machine learning based techniques, the proposed method shows outstanding performance without the requirement of perfect channel state information (CSI) and prohibitive computational complexity. Finally, the proposed method is robust in terms of the choice of channel parameters (e.g., number of paths) and also in terms of "generalization ability" from a machine learning standpoint., Comment: 13 pages, 12 figures, has been accepted for publication in IEEE Transactions on Cognitive Communications and Networking

Recently, machine learning-based channel estimation has attracted much attention. The performance of machine learning-based estimation has been validated by simulation experiments. However, little attention has been paid to the theoretical performance analysis. In this paper, we investigate the mean square error (MSE) performance of machine learning-based estimation. Hypothesis testing is employed to analyze its MSE upper bound. Furthermore, we build a statistical model for hypothesis testing, which holds when the linear learning module with a low input dimension is used in machine learning-based channel estimation, and derive a clear analytical relation between the size of the training data and performance. Then, we simulate the machine learning-based channel estimation in orthogonal frequency division multiplexing (OFDM) systems to verify our analysis results. Finally, the design considerations for the situation where only limited training data is available are discussed. In this situation, our analysis results can be applied to assess the performance and support the design of machine learning-based channel estimation., Comment: 11 pages, 10 figures. To appear in IEEE Transactions on Communications

The increasing emissions of carbon dioxide (CO2) are primarily driven by the rapid expansion of energy-intensive sectors such as the chemical industry. This work selects ethylene, one of the most important chemicals, as a model study to represent the low-carbon roadmap of chemical production. Four strategies, improving the efficiency of fossil resource usage, developing the technology for carbon capture and storage (CCS), CO2 chemical conversion, and converting biomass resources into chemicals, are used to reduce CO2 emissions. A comprehensive analysis of the life cycle CO2 emissions of different ethylene production routes has been performed to compare their emission reduction potential. The results indicate that the CO2MTO (CO2 to olefins via methanol-to-olefins) pathway releases the least CO2 (-0.05 t CO2/t ethylene), while the CFTO (coal to olefins via Fischer-Tropsch synthesis) possesses the most CO2 emissions. Combining CCS with BMTO (biomass to olefins via methanol-to-olefins) results in CO2 emissions of -6.0 t per t ethylene. Furthermore, we analysed the annual production and CO2 emissions of ethylene in the last 17 years and integrated this real-time change with different pathways. The CO2 emissions have decreased by 29.4% per t ethylene from 2000 to 2016 in China. However, the total amount of CO2 emissions continuously increase in the ethylene production industry. Given that China has promised to hit peak CO2 emissions by 2030, a scenario analysis was performed. To achieve this goal, the ratios of BMTO, CO2MTO or BETE (ethanol to ethylene pathway originating from biomass) pathways should increase by 0.9%, 1.4% and 1.6% annually from 2020, respectively. Then more than 700 million metric tons of CO2 will be eliminated from 2020 to 2040. The results highlight the pivotal role that regulation and policy administration can play in controlling CO2 emissions by increasing average technological level and turning to low-carbon routes in the chemical industry in Chin

The increasing emissions of carbon dioxide (CO2) are primarily driven by the rapid expansion of energy-intensive sectors such as the chemical industry. This work selects ethylene, one of the most important chemicals, as a model study to represent the low-carbon roadmap of chemical production. Four strategies, improving the efficiency of fossil resource usage, developing the technology for carbon capture and storage (CCS), CO2 chemical conversion, and converting biomass resources into chemicals, are used to reduce CO2 emissions. A comprehensive analysis of the life cycle CO2 emissions of different ethylene production routes has been performed to compare their emission reduction potential. The results indicate that the CO2MTO (CO2 to olefins via methanol-to-olefins) pathway releases the least CO2 (-0.05 t CO2/t ethylene), while the CFTO (coal to olefins via Fischer-Tropsch synthesis) possesses the most CO2 emissions. Combining CCS with BMTO (biomass to olefins via methanol-to-olefins) results in CO2 emissions of -6.0 t per t ethylene. Furthermore, we analysed the annual production and CO2 emissions of ethylene in the last 17 years and integrated this real-time change with different pathways. The CO2 emissions have decreased by 29.4% per t ethylene from 2000 to 2016 in China. However, the total amount of CO2 emissions continuously increase in the ethylene production industry. Given that China has promised to hit peak CO2 emissions by 2030, a scenario analysis was performed. To achieve this goal, the ratios of BMTO, CO2MTO or BETE (ethanol to ethylene pathway originating from biomass) pathways should increase by 0.9%, 1.4% and 1.6% annually from 2020, respectively. Then more than 700 million metric tons of CO2 will be eliminated from 2020 to 2040. The results highlight the pivotal role that regulation and policy administration can play in controlling CO2 emissions by increasing average technological level and turning to low-carbon routes in the chemical industry in Chin

Xiaochen Zhang,1,* Quan Yu,2,* Yan-an Wang,1 Jun Zhao2 1Department of Oral and Maxillofacial-Head and Neck Oncology, 2Department of Orthodontics, College of Stomatology, Ninth People’s Hospital, School of Medicine, Shanghai Jiao Tong University, Shanghai, China *These authors contributed equally to this work Introduction: To induce sufficient new bone formation, high doses of bone morphogenetic protein-2 (BMP-2) are applied in regenerative medicine that often induce serious side effects. Therefore, improved treatment strategies are required. Here, we investigate whether the delivery of BMP-2 lyophilized in the presence of trehalose reduced the dose of BMP-2 required for bone regeneration. Materials and methods: A new growth factor delivery system was fabricated using BMP-2-loaded TiO2 nanotubes by lyophilization with trehalose (TiO2-Lyo-Tre-BMP-2). We measured BMP-2 release characteristics, bioactivity, and stability, and determined the effects on the osteogenic differentiation of bone marrow stromal cells in vitro. Additionally, we evaluated the ability of this formulation to regenerate new bone around implants in rat femur defects by micro-computed tomography (micro-CT), sequential fluorescent labelling, and histological analysis. Results: Compared with absorbed BMP-2-loaded TiO2 nanotubes (TiO2-BMP-2), TiO2-Lyo-Tre-BMP-2 exhibited sustained release, consistent bioactivity, and higher stability of BMP-2, and resulted in greater osteogenic differentiation of BMSCs. Eight weeks post-operation, TiO2-Lyo-Tre-BMP-2 nanotubes, with various dosages of BMP-2, regenerated larger amounts of new bone than TiO2-BMP-2 nanotubes. Conclusion: Our findings indicate that delivery of BMP-2 lyophilized with trehalose may be a promising method to reduce the dose of BMP-2 and avoid the associated side effects. Keywords: bone morphogenetic protein-2, dose reduction, delivery system, trehalose, lyophilization, TiO2 nanotubes, BMP-2, regenerative medicine, sur

The increasing emissions of carbon dioxide (CO2) are primarily driven by the rapid expansion of energy-intensive sectors such as the chemical industry. This work selects ethylene, one of the most important chemicals, as a model study to represent the low-carbon roadmap of chemical production. Four strategies, improving the efficiency of fossil resource usage, developing the technology for carbon capture and storage (CCS), CO2 chemical conversion, and converting biomass resources into chemicals, are used to reduce CO2 emissions. A comprehensive analysis of the life cycle CO2 emissions of different ethylene production routes has been performed to compare their emission reduction potential. The results indicate that the CO2MTO (CO2 to olefins via methanol-to-olefins) pathway releases the least CO2 (-0.05 t CO2/t ethylene), while the CFTO (coal to olefins via Fischer-Tropsch synthesis) possesses the most CO2 emissions. Combining CCS with BMTO (biomass to olefins via methanol-to-olefins) results in CO2 emissions of -6.0 t per t ethylene. Furthermore, we analysed the annual production and CO2 emissions of ethylene in the last 17 years and integrated this real-time change with different pathways. The CO2 emissions have decreased by 29.4% per t ethylene from 2000 to 2016 in China. However, the total amount of CO2 emissions continuously increase in the ethylene production industry. Given that China has promised to hit peak CO2 emissions by 2030, a scenario analysis was performed. To achieve this goal, the ratios of BMTO, CO2MTO or BETE (ethanol to ethylene pathway originating from biomass) pathways should increase by 0.9%, 1.4% and 1.6% annually from 2020, respectively. Then more than 700 million metric tons of CO2 will be eliminated from 2020 to 2040. The results highlight the pivotal role that regulation and policy administration can play in controlling CO2 emissions by increasing average technological level and turning to low-carbon routes in the chemical industry in Chin

The increasing emissions of carbon dioxide (CO2) are primarily driven by the rapid expansion of energy-intensive sectors such as the chemical industry. This work selects ethylene, one of the most important chemicals, as a model study to represent the low-carbon roadmap of chemical production. Four strategies, improving the efficiency of fossil resource usage, developing the technology for carbon capture and storage (CCS), CO2 chemical conversion, and converting biomass resources into chemicals, are used to reduce CO2 emissions. A comprehensive analysis of the life cycle CO2 emissions of different ethylene production routes has been performed to compare their emission reduction potential. The results indicate that the CO2MTO (CO2 to olefins via methanol-to-olefins) pathway releases the least CO2 (-0.05 t CO2/t ethylene), while the CFTO (coal to olefins via Fischer-Tropsch synthesis) possesses the most CO2 emissions. Combining CCS with BMTO (biomass to olefins via methanol-to-olefins) results in CO2 emissions of -6.0 t per t ethylene. Furthermore, we analysed the annual production and CO2 emissions of ethylene in the last 17 years and integrated this real-time change with different pathways. The CO2 emissions have decreased by 29.4% per t ethylene from 2000 to 2016 in China. However, the total amount of CO2 emissions continuously increase in the ethylene production industry. Given that China has promised to hit peak CO2 emissions by 2030, a scenario analysis was performed. To achieve this goal, the ratios of BMTO, CO2MTO or BETE (ethanol to ethylene pathway originating from biomass) pathways should increase by 0.9%, 1.4% and 1.6% annually from 2020, respectively. Then more than 700 million metric tons of CO2 will be eliminated from 2020 to 2040. The results highlight the pivotal role that regulation and policy administration can play in controlling CO2 emissions by increasing average technological level and turning to low-carbon routes in the chemical industry in Chin

Xiaochen Zhang,1,* Quan Yu,2,* Yan-an Wang,1 Jun Zhao2 1Department of Oral and Maxillofacial-Head and Neck Oncology, 2Department of Orthodontics, College of Stomatology, Ninth People’s Hospital, School of Medicine, Shanghai Jiao Tong University, Shanghai, China *These authors contributed equally to this work Introduction: To induce sufficient new bone formation, high doses of bone morphogenetic protein-2 (BMP-2) are applied in regenerative medicine that often induce serious side effects. Therefore, improved treatment strategies are required. Here, we investigate whether the delivery of BMP-2 lyophilized in the presence of trehalose reduced the dose of BMP-2 required for bone regeneration. Materials and methods: A new growth factor delivery system was fabricated using BMP-2-loaded TiO2 nanotubes by lyophilization with trehalose (TiO2-Lyo-Tre-BMP-2). We measured BMP-2 release characteristics, bioactivity, and stability, and determined the effects on the osteogenic differentiation of bone marrow stromal cells in vitro. Additionally, we evaluated the ability of this formulation to regenerate new bone around implants in rat femur defects by micro-computed tomography (micro-CT), sequential fluorescent labelling, and histological analysis. Results: Compared with absorbed BMP-2-loaded TiO2 nanotubes (TiO2-BMP-2), TiO2-Lyo-Tre-BMP-2 exhibited sustained release, consistent bioactivity, and higher stability of BMP-2, and resulted in greater osteogenic differentiation of BMSCs. Eight weeks post-operation, TiO2-Lyo-Tre-BMP-2 nanotubes, with various dosages of BMP-2, regenerated larger amounts of new bone than TiO2-BMP-2 nanotubes. Conclusion: Our findings indicate that delivery of BMP-2 lyophilized with trehalose may be a promising method to reduce the dose of BMP-2 and avoid the associated side effects. Keywords: bone morphogenetic protein-2, dose reduction, delivery system, trehalose, lyophilization, TiO2 nanotubes, BMP-2, regenerative medicine, sur

In this letter, a novel synchronization method for MIMO-OFDM systems is proposed. The new approach has an accurate estimate of both symbol timing and large frequency offest. Simulation results show the excellent robustness of our method in double-selective channel even if the strongest multipath component arrives behind the first path., Comment: 2 pages letter with 4 figures

The combination of an increasing number of new cancer cases and improving survival rates has led to a large and rapidly growing population with unique health-care requirements. Exercise has been proposed as a strategy to help address the issues faced by cancer patients. Supported by a growing body of research, major health organizations commonly identify the importance of incorporating exercise in cancer care and advise patients to be physically active. This systematic review comprehensively summarizes the available epidemiologic and randomized controlled trial evidence investigating the role of exercise in the management of cancer. Literature searches focused on determining the potential impact of exercise on 1) cancer mortality and recurrence and 2) adverse effects of cancer and its treatment. A total of 100 studies were reviewed involving thousands of individual patients whose exercise behavior was assessed following the diagnosis of any type of cancer. Compared with patients who performed no/less exercise, patients who exercised following a diagnosis of cancer were observed to have a lower relative risk of cancer mortality and recurrence and experienced fewer/less severe adverse effects. The findings of this review support the view that exercise is an important adjunct therapy in the management of cancer. Implications on cancer care policy and practice are discussed.

The combination of an increasing number of new cancer cases and improving survival rates has led to a large and rapidly growing population with unique health-care requirements. Exercise has been proposed as a strategy to help address the issues faced by cancer patients. Supported by a growing body of research, major health organizations commonly identify the importance of incorporating exercise in cancer care and advise patients to be physically active. This systematic review comprehensively summarizes the available epidemiologic and randomized controlled trial evidence investigating the role of exercise in the management of cancer. Literature searches focused on determining the potential impact of exercise on 1) cancer mortality and recurrence and 2) adverse effects of cancer and its treatment. A total of 100 studies were reviewed involving thousands of individual patients whose exercise behavior was assessed following the diagnosis of any type of cancer. Compared with patients who performed no/less exercise, patients who exercised following a diagnosis of cancer were observed to have a lower relative risk of cancer mortality and recurrence and experienced fewer/less severe adverse effects. The findings of this review support the view that exercise is an important adjunct therapy in the management of cancer. Implications on cancer care policy and practice are discussed.

To diagnose rotating machinery fault for imbalanced data, a kind of method based on fast clustering algorithm and decision tree is proposed. Combined with wavelet packet decomposition and isometric mapping (Isomap), sensitive features of different faults can be obtained so the imbalanced fault sample set is constituted. Then the fast clustering algorithm is applied to search core samples from the majority data of the imbalanced fault sample set. Consequently, the balanced fault sample set consisted of the clustered data and the minority data is built. After that, decision tree is trained with the balanced fault sample set to get the fault diagnosis model. Finally, gearbox fault data set and rolling bearing fault data set are used to test the fault diagnosis model. The experiment results show that proposed fault diagnosis model could accurately diagnose the rotating machinery fault for imbalanced data.

Xiaochen Zhang,1 Zhiyuan Zhang,1 Gang Shen,2 Jun Zhao2 1Department of Oral and Maxillofacial Surgery, 2Department of Orthodontics, College of Stomatology, Ninth People’s Hospital, School of Medicine, Shanghai Jiao Tong University, Shanghai, People’s Republic of China Abstract: To enhance biocompatibility and osseointegration between titanium implants and surrounding bone tissue, numerous efforts have been made to modify the surface topography and composition of Ti implants. In this paper, Lenti-BMP-2-loaded TiO2 nanotube coatings were fabricated by lyophilization in the presence of trehalose to functionalize the surface. We characterized TiO2 nanotube layers in terms of the following: surface morphology; Lenti-BMP-2 and trehalose release; their ability to induce osteogenesis, proliferation, and anti-inflammation in vitro; and osseointegration in vivo. The anodized TiO2 nanotube surfaces exhibited an amorphous glassy matrix perpendicular to the Ti surface. Both Lenti-BMP-2 and trehalose showed sustained release over the course of 8 days. Results from real-time quantitative polymerase chain reaction studies demonstrated that lyophilized Lenti-BMP-2/TiO2 nanotubes constructed with trehalose (Lyo-Tre-Lenti-BMP-2) significantly promoted osteogenic differentiation of bone marrow stromal cells but not their proliferation. In addition, Lyo-Tre-Lenti-BMP-2 nanotubes effectively inhibited lipopolysaccharide-induced interleukin-1β and tumor necrosis factor-α production. In vivo, the formulation also promoted osseointegration. This study presents a promising new method for surface-modifying biomedical Ti-based implants to simultaneously enhance their osteogenic potential and anti-inflammatory properties, which can better satisfy clinical needs. Keywords: osteogenesis, anti-inflammation, TiO2 nanotube layers, Lenti-BMP-2, lyophilization, trehalose&nbsp

Xiaochen Zhang,1 Zhiyuan Zhang,1 Gang Shen,2 Jun Zhao2 1Department of Oral and Maxillofacial Surgery, 2Department of Orthodontics, College of Stomatology, Ninth People’s Hospital, School of Medicine, Shanghai Jiao Tong University, Shanghai, People’s Republic of China Abstract: To enhance biocompatibility and osseointegration between titanium implants and surrounding bone tissue, numerous efforts have been made to modify the surface topography and composition of Ti implants. In this paper, Lenti-BMP-2-loaded TiO2 nanotube coatings were fabricated by lyophilization in the presence of trehalose to functionalize the surface. We characterized TiO2 nanotube layers in terms of the following: surface morphology; Lenti-BMP-2 and trehalose release; their ability to induce osteogenesis, proliferation, and anti-inflammation in vitro; and osseointegration in vivo. The anodized TiO2 nanotube surfaces exhibited an amorphous glassy matrix perpendicular to the Ti surface. Both Lenti-BMP-2 and trehalose showed sustained release over the course of 8 days. Results from real-time quantitative polymerase chain reaction studies demonstrated that lyophilized Lenti-BMP-2/TiO2 nanotubes constructed with trehalose (Lyo-Tre-Lenti-BMP-2) significantly promoted osteogenic differentiation of bone marrow stromal cells but not their proliferation. In addition, Lyo-Tre-Lenti-BMP-2 nanotubes effectively inhibited lipopolysaccharide-induced interleukin-1β and tumor necrosis factor-α production. In vivo, the formulation also promoted osseointegration. This study presents a promising new method for surface-modifying biomedical Ti-based implants to simultaneously enhance their osteogenic potential and anti-inflammatory properties, which can better satisfy clinical needs. Keywords: osteogenesis, anti-inflammation, TiO2 nanotube layers, Lenti-BMP-2, lyophilization, trehalose&nbsp

To predict residual lifetime of ball screw, screw lifetime prediction technology based on wavelet neural network (WNN) and empirical mode decomposition (EMD) is proposed. Screw accelerated lifetime test platform is introduced. Accelerometers are installed to monitor ball screw lifetime. With the method of principal component analysis (PCA), high dimension features are mapped to low dimensional space and stored into sample library together with screw expected remaining lifetime. Training samples and testing samples are randomly selected from the sample library to train and test the WNN. Then EMD is used to extract output tendency of WNN. Finally, screw lifetime prediction model can be obtained. The experimental results show that the maximum error of the training samples is 602 hours while the maximum error of the testing samples is 652 hours, which meet the need of screw lifetime prediction.

The Internet is experiencing an explosion of information presented in different languages. Though written in different languages, some articles implicitly share common concepts. In this paper, we propose a novel framework to mine cross- language common concepts from unaligned web documents. Specifically, visual words of images are used to bridge articles in different languages and then common concepts of multiple languages are learned by using an existing topic modeling algorithm. We conduct cross-lingual text classification in a real-world data set using the mined multilingual concepts from our method. The experiment results show that our approach is effective to mine cross-lingual common concepts.

The Internet is experiencing an explosion of information presented in different languages. Though written in different languages, some articles implicitly share common concepts. In this paper, we propose a novel framework to mine cross- language common concepts from unaligned web documents. Specifically, visual words of images are used to bridge articles in different languages and then common concepts of multiple languages are learned by using an existing topic modeling algorithm. We conduct cross-lingual text classification in a real-world data set using the mined multilingual concepts from our method. The experiment results show that our approach is effective to mine cross-lingual common concepts.

Wearable robotic exoskeletons have been explored for their efficacy in physical rehabilitation and for assistance in daily activites in people with motor disorders. The concept of human-in-the-loop optimization has been used to identify ideal exoskeleton assistive torques based on measured individual performance metrics, for instance, metabolic cost, but few studies have attempted to optimize several performance metrics simultaneously.We have previously developed a cable-driven ankle exoskeleton that can provide assistance to the ankle in both sagittal and frontal planes, aimed for persons with dropfoot and excessive inversion. In this study, we propose a multi-objective human-in-the-loop optimization that identifies the ankle exoskeleton properties that improve gait quality, defined here as normal foot segment kinematics and step length symmetry. One able-bodied subject tested the feasibility of the proposed method. The subject wore the exoskeleton while walking on a treadmill. An extra weight was attached on the right foot to simulate the gait deviations associated with dropfoot and excessive inversion. The Pareto front, comprising six results, was sorted, which illustrated the improvement in both foot segment kinematics and step length symmetry. Within this set of results, each represents a unique compromise or balance between the two objectives, and it was observed that enhancing step length symmetry might lead to an increase in foot segment deviation, showcasing the inherent trade-off relationship between these two aspects.These results suggest that this method can potentially be useful in determining subject-specific exoskeleton control laws that improve several measures of gait in persons with gait disability., QC 20231120

Wearable exoskeletons are emerging technologies for providing movement assistance and rehabilitation for people with motor disorders. In this study, we focus on the specific gait pathology dropfoot, which is common after a stroke. Dropfoot makes it difficult to achieve foot clearance during swing and heel contact at early stance and often necessitates compensatory movements. We developed a soft ankle exoskeleton consisting of actuation and transmission systems to assist two degrees of freedom simultaneously, dorsiflexion and eversion. The actuation system consists of two motors worn on a waist belt. The assistive force is transmitted to the medial and lateral sides of the forefoot via Bowden cables. The coupling design enables variable assistance of dorsiflexion and inversion at the same time. As a proof-of-concept study, we evaluated the performance of the exoskeleton on five able-bodied subjects in three movement cases - assisting dorsiflexion and eversion, controlling plantarflexion, and compensating for device resistance. In the first two cases, errors between the desired and the achieved ankle joints in two DoFs were low; errors of < 1.5° were achieved in assisting dorsiflexion and/or controlling plantarflexion, and of < 1.4° in assisting ankleeversion. The proposed force-free controller in case 3 significantly compensated for the device resistance during ankle joint plantarflexion. Our findings support the feasibility of the new ankle exoskeleton design in assisting two degrees of freedom at the ankle simultaneously., QC 20231120

Cormie, P., Zopf, E. M., Zhang, X., & Schmitz, K. H. (2017). The impact of exercise on cancer mortality, recurrence, and treatment-related adverse effects. Epidemiologic reviews, 39(1), 71-92. doi:here.