Wnt signaling transduces evolutionarily conserved pathways which play important roles in initiating and regulating a diverse range of cellular activities,including cell proliferation,calcium homeostasis,and cell polar...Wnt signaling transduces evolutionarily conserved pathways which play important roles in initiating and regulating a diverse range of cellular activities,including cell proliferation,calcium homeostasis,and cell polarity.The role of Wnt signaling in controlling cell proliferation and stem cell self-renewal is primarily carried out through the canonical pathway,which is the best-characterized the multiple Wnt signaling branches.The past 10 years has seen a rapid expansion in our understanding of the complexity of this pathway,as many new components of Wnt signaling have been identified and linked to signaling regulation,stem cell functions,and adult tissue homeostasis.Additionally,a substantial body of evidence links Wnt signaling to tumorigenesis of cancer types and implicates it in the development of cancer drug resistance.Thus,a better understanding of the mechanisms by which dysregulation of Wnt signaling precedes the development and progression of human cancer may hasten the development of pathway inhibitors to augment current therapy.This review summarizes and synthesizes our current knowledge of the canonical Wnt pathway in development and disease.We begin with an overview of the components of the canonical Wnt signaling pathway and delve into the role this pathway has been shown to play in stemness,tumorigenesis,and cancer drug resistance.Ultimately,we hope to present an organized collection of evidence implicating Wnt signaling in tumorigenesis and chemoresistance to facilitate the pursuit of Wnt pathway modulators that may improve outcomes of cancers in which Wnt signaling contributes to aggressive disease and/or treatment resistance.展开更多
The manipulation and characterization of light polarization states are essential for many applications in quantum communication and computing,spectroscopy,bioinspired navigation,and imaging.Chiral metamaterials and me...The manipulation and characterization of light polarization states are essential for many applications in quantum communication and computing,spectroscopy,bioinspired navigation,and imaging.Chiral metamaterials and metasurfaces facilitate ultracompact devices for circularly polarized light generation,manipulation,and detection.Herein,we report bioinspired chiral metasurfaces with both strong chiral optical effects and low insertion loss.We experimentally demonstrated submicron-thick circularly polarized light filters with peak extinction ratios up to 35 and maximum transmission efficiencies close to 80% at near-infrared wavelengths(the best operational wavelengths can be engineered in the range of 1.3-1.6μm).We also monolithically integrated the microscale circular polarization filters with linear polarization filters to perform full-Stokes polarimetric measurements of light with arbitrary polarization states.With the advantages of easy on-chip integration,ultracompact footprints,scalability,and broad wavelength coverage,our designs hold great promise for facilitating chip-integrated polarimeters and polarimetric imaging systems for quantum-based optical computing and information processing,circular dichroism spectroscopy,biomedical diagnosis,and remote sensing applications.展开更多
The Joint Automated Repository for Various Integrated Simulations(JARVIS)is an integrated infrastructure to accelerate materials discovery and design using density functional theory(DFT),classical force-fields(FF),and...The Joint Automated Repository for Various Integrated Simulations(JARVIS)is an integrated infrastructure to accelerate materials discovery and design using density functional theory(DFT),classical force-fields(FF),and machine learning(ML)techniques.JARVIS is motivated by the Materials Genome Initiative(MGI)principles of developing open-access databases and tools to reduce the cost and development time of materials discovery,optimization,and deployment.展开更多
Reactive oxygen and nitrogen species (RONS) are essential for normal physiological processes and play important roles in cell signaling, immunity, and tissue homeostasis. However, excess radical species are implicat...Reactive oxygen and nitrogen species (RONS) are essential for normal physiological processes and play important roles in cell signaling, immunity, and tissue homeostasis. However, excess radical species are implicated in the development and augmented pathogenesis of various diseases. Several antioxidants may restore the chemical balance, but their use is limited by disappointing results of clinical trials. Nanoparticles are an attractive therapeutic alternative because they can change the biodistribution profile of antioxidants, and possess intrinsic ability to scavenge RONS. Herein, we review the types of RONS, how they are implicated in several diseases, and the types of nanoparticles with inherent antioxidant capability, their mechanisms of action, and their biological applications.展开更多
Cohesive scientific evidence from molecular, animal, and human investigations supports the hypothesis that constitutive overexpression of cyclooxygenase-2(COX-2) is a ubiquitous driver of mammary carcinogenesis, and r...Cohesive scientific evidence from molecular, animal, and human investigations supports the hypothesis that constitutive overexpression of cyclooxygenase-2(COX-2) is a ubiquitous driver of mammary carcinogenesis, and reciprocally, that COX-2 blockade has strong potential for breast cancer prevention and therapy. Key findings include the following:(1) COX-2 is constitutively expressed throughout breast cancer development and expression intensifies with stage at detection, cancer progression and metastasis;(2) essential features of mammary carcinogenesis(mutagenesis, mitogenesis, angiogenesis, reduced apoptosis, metastasis and immunosuppression) are linked to COX-2-driven prostaglandin E2(PGE-2) biosynthesis;(3) upregulation of COX-2 and PGE-2 expression induces transcription of CYP-19 and aromatase-catalyzed estrogen biosynthesis which stimulates unbridled mitogenesis;(4) extrahe-patic CYP-1B1 in mammary adipose tissue converts paracrine estrogen to carcinogenic quinones with mutagenic impact; and(5) agents that inhibit COX-2 reduce the risk of breast cancer in women without disease and reduce recurrence risk and mortality in women with breast cancer. Recent sharp increases in global breast cancer incidence and mortality are likely driven by chronic inflammation of mammary adipose and upregulation of COX-2 associated with the obesity pandemic. The totality of evidence clearly supports the supposition that mammary carcinogenesis often evolves as a progressive series of highly specific cellular and molecular changes in response to induction of constitutive overexpression of COX-2 and the prostaglandin cascade in the "inflammogenesis of breast cancer".展开更多
The effective mass is a convenient descriptor of the electronic band structure used to characterize the density of states and electron transport based on a free electron model.While effective mass is an excellent firs...The effective mass is a convenient descriptor of the electronic band structure used to characterize the density of states and electron transport based on a free electron model.While effective mass is an excellent first-order descriptor in real systems,the exact value can have several definitions,each of which describe a different aspect of electron transport.Here we use Boltzmann transport calculations applied to ab initio band structures to extract a density-of-states effective mass from the Seebeck Coefficient and an inertial mass from the electrical conductivity to characterize the band structure irrespective of the exact scattering mechanism.We identify a Fermi Surface Complexity Factor:N_(v)^(*)K^(*) from the ratio of these two masses,which in simple cases depends on the number of Fermi surface pockets eN_(v)^(*) T and their anisotropy K^(*),both of which are beneficial to high thermoelectric performance as exemplified by the high values found in PbTe.The Fermi Surface Complexity factor can be used in high-throughput search of promising thermoelectric materials.展开更多
Background: Few school settings offer opportunities for preschool children to engage in structured physical activity, and only a few studies have been conducted examining exergaming's effectiveness on health outco...Background: Few school settings offer opportunities for preschool children to engage in structured physical activity, and only a few studies have been conducted examining exergaming's effectiveness on health outcomes in this age group. This study's purpose, therefore, was to examine a school-based exergaming intervention's effect on preschool children's perceived competence(PC), motor skill competence(MSC), and physical activity versus usual care(recess), as well as to examine gender differences for these outcomes.Methods: A total of 65 preschool children from 2 underserved urban schools were assigned to 1 of 2 conditions, with the school as the experimental unit:(1) usual care recess group(8 weeks of 100 min of recess/week(5 days £ 20 min)) and(2) exergaming intervention group(8 weeks of100 min of exergaming/week(5 days £ 20 min) at school). All children underwent identical assessments of PC, MSC, and moderate-to-vigorous physical activity(MVPA) at baseline and at the end of the 8 th week.Results: A significant Group £ Time effect was observed for MVPA, F(1, 52) = 4.37, p = 0.04, h2 p= 0.04, but not for PC, F(1, 52) = 0.83, p = 0.37,h2 p= 0.02, or MSC, F(1, 52) = 0.02, p = 0.88, h2 p= 0.00. Specifically, the intervention children displayed significantly greater increased MVPA after8 weeks than the comparison children. Additionally, there was a significant time effect for MSC, F(1, 52) = 15.61, p < 0.01, h2 p= 0.23, and gender effect for MVPA, F(1, 52) = 5.06, p = 0.02, h2 p= 0.09. Although all preschoolers' MSC improved across time, boys demonstrated greater MVPA than girls at both time points.Conclusion: Exergaming showed a positive effect in promoting preschool children's MVPA at school and has the potential to enhance PC and MSC. More research with larger sample sizes and longer study durations are warranted.展开更多
This review highlights the recent evolution of the imaging,medical management,surgical options and endovascular therapies for symptomatic intracranial atherosclerotic disease(ICAD).Recent imaging developments includin...This review highlights the recent evolution of the imaging,medical management,surgical options and endovascular therapies for symptomatic intracranial atherosclerotic disease(ICAD).Recent imaging developments including optical coherence tomography and other modalities to assess the intracranial arteries for symptomatic ICAD are reviewed,not only to diagnose ICAD but to determine if ICAD plaques have any high-risk features for treatment.Potential future developments in the treatment of ICAD are discussed,including the development of trackable drug-coated balloons for the cerebral circulation to treat primary or restenotic arteries,new iterations of self-expanding intracranial stents with easier delivery systems,and the re-examination of indirect surgical bypass techniques for revascularisation.In addition to these important technological developments,however,is the evolving evidence regarding the best treatment window for these techniques and additional factors in medical management which can improve patient outcomes in this devastating pathology.展开更多
Purpose: To examine, within a social–ecological framework, associations between multifaceted individual and environmental factors and habitual physical activity(HPA) among older Chinese adults.Methods: Through a mix ...Purpose: To examine, within a social–ecological framework, associations between multifaceted individual and environmental factors and habitual physical activity(HPA) among older Chinese adults.Methods: Through a mix of qualitative and quantitative methods, a survey instrument assessing various factors underlying 3 social–ecological dimensions of intrapersonal, interpersonal, and community and environmental resources was developed. Using a cross-sectional design, older adults(n = 1580, aged 67 ± 7 years) recruited from 10 communities in Shandong province completed the social–ecological survey of HPA. Data were analyzed using Partial Least Squares Path Modeling.Results: Factors related to intrapersonal(medical knowledge, motivation, physical function, sport skills, socioeconomic status, and education),interpersonal(social support, social activity, and social norms), and community and physical environmental resources(safety, capacity, availability of and access to physical activity facilities) were found to be significantly associated with older adults' participation in HPA.Conclusion: The findings provide an initial validation of a social–ecological approach to the study of HPA in China, suggesting that strategies aimed at promoting physical activity in older adults should address multiple levels of factors that may contribute to the likelihood of older Chinese adults being physically active.展开更多
The rapid growth of social networks has produced an unprecedented amount of user-generated data, which provides an excellent opportunity for text mining. Authorship analysis, an important part of text mining, attempts...The rapid growth of social networks has produced an unprecedented amount of user-generated data, which provides an excellent opportunity for text mining. Authorship analysis, an important part of text mining, attempts to learn about the author of the text through subtle variations in the writing styles that occur between gender, age and social groups. Such information has a variety of applications including advertising and law enforcement. One of the most accessible sources of user-generated data is Twitter, which makes the majority of its user data freely available through its data access API. In this study we seek to identify the gender of users on Twitter using Perceptron and Nai ve Bayes with selected 1 through 5-gram features from tweet text. Stream applications of these algorithms were employed for gender prediction to handle the speed and volume of tweet traffic. Because informal text, such as tweets, cannot be easily evaluated using traditional dictionary methods, n-gram features were implemented in this study to represent streaming tweets. The large number of 1 through 5-grams requires that only a subset of them be used in gender classification, for this reason informative n-gram features were chosen using multiple selection algorithms. In the best case the Naive Bayes and Perceptron algorithms produced accuracy, balanced accuracy, and F-measure above 99%.展开更多
Background: Players may not acquire adequate levels of moderate-to-vigorous physical activity(MVPA) when playing commercial video games.This study's goal was to evaluate the effects of an exercise bike video game ...Background: Players may not acquire adequate levels of moderate-to-vigorous physical activity(MVPA) when playing commercial video games.This study's goal was to evaluate the effects of an exercise bike video game played by using a mobile application-based exergame that was designed exclusively to promote participants' MVPA, with additional attention paid to this game's ability to promote greater situational interest.Methods: An experimental design was used with 163 students(aged 20.31 ± 1.30, 18–26 years, 61.3% male), all of whom were randomly allocated into an experimental group and a control group. Physical activity(PA) levels were assessed with Acti Graph GT3X+(Acti Graph Inc., Fort Walton Beach, FL, USA) accelerometers. The situational interest scale was used to evaluate students' situational interest in both groups.Multivariate analysis of variance was conducted to examine the differences between sedentary behavior, PA levels, and situational interest between groups. Regression analyses were also used, with the purpose being to evaluate the strength of the relationship between PA and situational interest.Results: Results revealed that the experimental group had higher degrees of sedentary behavior, light PA, total interest, instant enjoyment,exploration intention, attention demand, novelty, and challenge, whereas the control group received higher scores for MVPA(control 95.01% vs.experimental group 89.94%). Regression analysis indicated that instant enjoyment(β = 0.49, p < 0.01), exploration intention(β = 0.18, p < 0.05),and attention demand(β = 0.17, p < 0.05) were positive predictors for total interest, explaining 43% of its variance.Conclusion: A newly designed mobile application-based exergame played via an exercise bike may enhance situational interest and provide a decent level of PA for players.展开更多
Historically, the most common mechanism of total kneearthroplasty(TKA) failures included aseptic loosening, instability and malalignment. As polyethylene production improved, modes of failure from polyethylene wear an...Historically, the most common mechanism of total kneearthroplasty(TKA) failures included aseptic loosening, instability and malalignment. As polyethylene production improved, modes of failure from polyethylene wear and subsequent osteolysis became less prevalent. Newer longitudinal studies report that infection has become the primary acute cause of failure with loosening and instability remaining as the overall greatest reasons for revision. Clinical database and worldwide national registries confirm these reports. With an increasing amount of TKA operations performed in the United States, and with focus on value-based healthcare, it is imperative to understand why total knees fail.展开更多
基金The authors’research efforts were supported in part by research grants from the NIH(AT004418 to TCH)the 973 Program of Ministry of Science and Technology(MOST)of China(#2011CB707900 to TCH)+1 种基金the Scoliosis Research Society(to MJL),MKM was a recipient of Howard Hughes Medical Institute Medical Research FellowshipCS was a recipient of the Pritzker Summer Research Fellowship funded through a NIH T-35 training grant(NIDDK).
文摘Wnt signaling transduces evolutionarily conserved pathways which play important roles in initiating and regulating a diverse range of cellular activities,including cell proliferation,calcium homeostasis,and cell polarity.The role of Wnt signaling in controlling cell proliferation and stem cell self-renewal is primarily carried out through the canonical pathway,which is the best-characterized the multiple Wnt signaling branches.The past 10 years has seen a rapid expansion in our understanding of the complexity of this pathway,as many new components of Wnt signaling have been identified and linked to signaling regulation,stem cell functions,and adult tissue homeostasis.Additionally,a substantial body of evidence links Wnt signaling to tumorigenesis of cancer types and implicates it in the development of cancer drug resistance.Thus,a better understanding of the mechanisms by which dysregulation of Wnt signaling precedes the development and progression of human cancer may hasten the development of pathway inhibitors to augment current therapy.This review summarizes and synthesizes our current knowledge of the canonical Wnt pathway in development and disease.We begin with an overview of the components of the canonical Wnt signaling pathway and delve into the role this pathway has been shown to play in stemness,tumorigenesis,and cancer drug resistance.Ultimately,we hope to present an organized collection of evidence implicating Wnt signaling in tumorigenesis and chemoresistance to facilitate the pursuit of Wnt pathway modulators that may improve outcomes of cancers in which Wnt signaling contributes to aggressive disease and/or treatment resistance.
基金supported in part by the AFOSR YIP under grant no.FA9550-16-1-0183the National Science Foundation under grant no.1809997+2 种基金partial support from the National Science Foundation under grant no.1711412Arizona State University startup funds provided to C.W.supported,in part,by NSF contract ECCS-1542160.
文摘The manipulation and characterization of light polarization states are essential for many applications in quantum communication and computing,spectroscopy,bioinspired navigation,and imaging.Chiral metamaterials and metasurfaces facilitate ultracompact devices for circularly polarized light generation,manipulation,and detection.Herein,we report bioinspired chiral metasurfaces with both strong chiral optical effects and low insertion loss.We experimentally demonstrated submicron-thick circularly polarized light filters with peak extinction ratios up to 35 and maximum transmission efficiencies close to 80% at near-infrared wavelengths(the best operational wavelengths can be engineered in the range of 1.3-1.6μm).We also monolithically integrated the microscale circular polarization filters with linear polarization filters to perform full-Stokes polarimetric measurements of light with arbitrary polarization states.With the advantages of easy on-chip integration,ultracompact footprints,scalability,and broad wavelength coverage,our designs hold great promise for facilitating chip-integrated polarimeters and polarimetric imaging systems for quantum-based optical computing and information processing,circular dichroism spectroscopy,biomedical diagnosis,and remote sensing applications.
基金K.C.thanks the computational support from XSEDE computational resources under allocation number TGDMR 190095Contributions from K.C.were supported by the financial assistance award 70NANB19H117 from the U.S.Department of Commerce,National Institute of Standards and Technology+3 种基金Contributions by S.M.,K.H.,K.R.,and D.V.were supported by NSF DMREF Grant No.DMR-1629059 and No.DMR-1629346X.Q.was supported by NSF Grant No.OAC-1835690A.A.acknowledges partial support by CHiMaD(NIST award#70NANB19H005)G.P.was supported by the Los Alamos National Laboratory’s Laboratory Directed Research and Development(LDRD)program’s Directed Research(DR)project#20200104DR。
文摘The Joint Automated Repository for Various Integrated Simulations(JARVIS)is an integrated infrastructure to accelerate materials discovery and design using density functional theory(DFT),classical force-fields(FF),and machine learning(ML)techniques.JARVIS is motivated by the Materials Genome Initiative(MGI)principles of developing open-access databases and tools to reduce the cost and development time of materials discovery,optimization,and deployment.
文摘Reactive oxygen and nitrogen species (RONS) are essential for normal physiological processes and play important roles in cell signaling, immunity, and tissue homeostasis. However, excess radical species are implicated in the development and augmented pathogenesis of various diseases. Several antioxidants may restore the chemical balance, but their use is limited by disappointing results of clinical trials. Nanoparticles are an attractive therapeutic alternative because they can change the biodistribution profile of antioxidants, and possess intrinsic ability to scavenge RONS. Herein, we review the types of RONS, how they are implicated in several diseases, and the types of nanoparticles with inherent antioxidant capability, their mechanisms of action, and their biological applications.
文摘Cohesive scientific evidence from molecular, animal, and human investigations supports the hypothesis that constitutive overexpression of cyclooxygenase-2(COX-2) is a ubiquitous driver of mammary carcinogenesis, and reciprocally, that COX-2 blockade has strong potential for breast cancer prevention and therapy. Key findings include the following:(1) COX-2 is constitutively expressed throughout breast cancer development and expression intensifies with stage at detection, cancer progression and metastasis;(2) essential features of mammary carcinogenesis(mutagenesis, mitogenesis, angiogenesis, reduced apoptosis, metastasis and immunosuppression) are linked to COX-2-driven prostaglandin E2(PGE-2) biosynthesis;(3) upregulation of COX-2 and PGE-2 expression induces transcription of CYP-19 and aromatase-catalyzed estrogen biosynthesis which stimulates unbridled mitogenesis;(4) extrahe-patic CYP-1B1 in mammary adipose tissue converts paracrine estrogen to carcinogenic quinones with mutagenic impact; and(5) agents that inhibit COX-2 reduce the risk of breast cancer in women without disease and reduce recurrence risk and mortality in women with breast cancer. Recent sharp increases in global breast cancer incidence and mortality are likely driven by chronic inflammation of mammary adipose and upregulation of COX-2 associated with the obesity pandemic. The totality of evidence clearly supports the supposition that mammary carcinogenesis often evolves as a progressive series of highly specific cellular and molecular changes in response to induction of constitutive overexpression of COX-2 and the prostaglandin cascade in the "inflammogenesis of breast cancer".
基金intellectually led by the Materials Project which is supported by the Department of Energy Basic Energy Sciences program under Grant No.EDCBEE,DOE Contract DE-AC02-05CH11231supported by the Office of Science of the U.S.Department of Energysupported by the F.R.S.-FNRS project HTBaSE(contract no.PDR-T.1071.15)。
文摘The effective mass is a convenient descriptor of the electronic band structure used to characterize the density of states and electron transport based on a free electron model.While effective mass is an excellent first-order descriptor in real systems,the exact value can have several definitions,each of which describe a different aspect of electron transport.Here we use Boltzmann transport calculations applied to ab initio band structures to extract a density-of-states effective mass from the Seebeck Coefficient and an inertial mass from the electrical conductivity to characterize the band structure irrespective of the exact scattering mechanism.We identify a Fermi Surface Complexity Factor:N_(v)^(*)K^(*) from the ratio of these two masses,which in simple cases depends on the number of Fermi surface pockets eN_(v)^(*) T and their anisotropy K^(*),both of which are beneficial to high thermoelectric performance as exemplified by the high values found in PbTe.The Fermi Surface Complexity factor can be used in high-throughput search of promising thermoelectric materials.
基金国家自然科学基金(No.30470252)East Asia and Pacific Summer Institutes providedto ZIF by the United States National Science Foundation中国科学院成都生物研究所知识创新工程领域前沿项目(CIB-2007-LYQY-Q02)共同资助~~
基金funded by a grant from the National Institutes of Health (No. 1R56HL130078-01)
文摘Background: Few school settings offer opportunities for preschool children to engage in structured physical activity, and only a few studies have been conducted examining exergaming's effectiveness on health outcomes in this age group. This study's purpose, therefore, was to examine a school-based exergaming intervention's effect on preschool children's perceived competence(PC), motor skill competence(MSC), and physical activity versus usual care(recess), as well as to examine gender differences for these outcomes.Methods: A total of 65 preschool children from 2 underserved urban schools were assigned to 1 of 2 conditions, with the school as the experimental unit:(1) usual care recess group(8 weeks of 100 min of recess/week(5 days £ 20 min)) and(2) exergaming intervention group(8 weeks of100 min of exergaming/week(5 days £ 20 min) at school). All children underwent identical assessments of PC, MSC, and moderate-to-vigorous physical activity(MVPA) at baseline and at the end of the 8 th week.Results: A significant Group £ Time effect was observed for MVPA, F(1, 52) = 4.37, p = 0.04, h2 p= 0.04, but not for PC, F(1, 52) = 0.83, p = 0.37,h2 p= 0.02, or MSC, F(1, 52) = 0.02, p = 0.88, h2 p= 0.00. Specifically, the intervention children displayed significantly greater increased MVPA after8 weeks than the comparison children. Additionally, there was a significant time effect for MSC, F(1, 52) = 15.61, p < 0.01, h2 p= 0.23, and gender effect for MVPA, F(1, 52) = 5.06, p = 0.02, h2 p= 0.09. Although all preschoolers' MSC improved across time, boys demonstrated greater MVPA than girls at both time points.Conclusion: Exergaming showed a positive effect in promoting preschool children's MVPA at school and has the potential to enhance PC and MSC. More research with larger sample sizes and longer study durations are warranted.
文摘This review highlights the recent evolution of the imaging,medical management,surgical options and endovascular therapies for symptomatic intracranial atherosclerotic disease(ICAD).Recent imaging developments including optical coherence tomography and other modalities to assess the intracranial arteries for symptomatic ICAD are reviewed,not only to diagnose ICAD but to determine if ICAD plaques have any high-risk features for treatment.Potential future developments in the treatment of ICAD are discussed,including the development of trackable drug-coated balloons for the cerebral circulation to treat primary or restenotic arteries,new iterations of self-expanding intracranial stents with easier delivery systems,and the re-examination of indirect surgical bypass techniques for revascularisation.In addition to these important technological developments,however,is the evolving evidence regarding the best treatment window for these techniques and additional factors in medical management which can improve patient outcomes in this devastating pathology.
基金supported by grant from the Ministry of Science and Technology of China (2015FY111600)
文摘Purpose: To examine, within a social–ecological framework, associations between multifaceted individual and environmental factors and habitual physical activity(HPA) among older Chinese adults.Methods: Through a mix of qualitative and quantitative methods, a survey instrument assessing various factors underlying 3 social–ecological dimensions of intrapersonal, interpersonal, and community and environmental resources was developed. Using a cross-sectional design, older adults(n = 1580, aged 67 ± 7 years) recruited from 10 communities in Shandong province completed the social–ecological survey of HPA. Data were analyzed using Partial Least Squares Path Modeling.Results: Factors related to intrapersonal(medical knowledge, motivation, physical function, sport skills, socioeconomic status, and education),interpersonal(social support, social activity, and social norms), and community and physical environmental resources(safety, capacity, availability of and access to physical activity facilities) were found to be significantly associated with older adults' participation in HPA.Conclusion: The findings provide an initial validation of a social–ecological approach to the study of HPA in China, suggesting that strategies aimed at promoting physical activity in older adults should address multiple levels of factors that may contribute to the likelihood of older Chinese adults being physically active.
文摘The rapid growth of social networks has produced an unprecedented amount of user-generated data, which provides an excellent opportunity for text mining. Authorship analysis, an important part of text mining, attempts to learn about the author of the text through subtle variations in the writing styles that occur between gender, age and social groups. Such information has a variety of applications including advertising and law enforcement. One of the most accessible sources of user-generated data is Twitter, which makes the majority of its user data freely available through its data access API. In this study we seek to identify the gender of users on Twitter using Perceptron and Nai ve Bayes with selected 1 through 5-gram features from tweet text. Stream applications of these algorithms were employed for gender prediction to handle the speed and volume of tweet traffic. Because informal text, such as tweets, cannot be easily evaluated using traditional dictionary methods, n-gram features were implemented in this study to represent streaming tweets. The large number of 1 through 5-grams requires that only a subset of them be used in gender classification, for this reason informative n-gram features were chosen using multiple selection algorithms. In the best case the Naive Bayes and Perceptron algorithms produced accuracy, balanced accuracy, and F-measure above 99%.
基金funded by a grant from the Brittany House of Human Sciences(2015–2017)
文摘Background: Players may not acquire adequate levels of moderate-to-vigorous physical activity(MVPA) when playing commercial video games.This study's goal was to evaluate the effects of an exercise bike video game played by using a mobile application-based exergame that was designed exclusively to promote participants' MVPA, with additional attention paid to this game's ability to promote greater situational interest.Methods: An experimental design was used with 163 students(aged 20.31 ± 1.30, 18–26 years, 61.3% male), all of whom were randomly allocated into an experimental group and a control group. Physical activity(PA) levels were assessed with Acti Graph GT3X+(Acti Graph Inc., Fort Walton Beach, FL, USA) accelerometers. The situational interest scale was used to evaluate students' situational interest in both groups.Multivariate analysis of variance was conducted to examine the differences between sedentary behavior, PA levels, and situational interest between groups. Regression analyses were also used, with the purpose being to evaluate the strength of the relationship between PA and situational interest.Results: Results revealed that the experimental group had higher degrees of sedentary behavior, light PA, total interest, instant enjoyment,exploration intention, attention demand, novelty, and challenge, whereas the control group received higher scores for MVPA(control 95.01% vs.experimental group 89.94%). Regression analysis indicated that instant enjoyment(β = 0.49, p < 0.01), exploration intention(β = 0.18, p < 0.05),and attention demand(β = 0.17, p < 0.05) were positive predictors for total interest, explaining 43% of its variance.Conclusion: A newly designed mobile application-based exergame played via an exercise bike may enhance situational interest and provide a decent level of PA for players.
文摘Historically, the most common mechanism of total kneearthroplasty(TKA) failures included aseptic loosening, instability and malalignment. As polyethylene production improved, modes of failure from polyethylene wear and subsequent osteolysis became less prevalent. Newer longitudinal studies report that infection has become the primary acute cause of failure with loosening and instability remaining as the overall greatest reasons for revision. Clinical database and worldwide national registries confirm these reports. With an increasing amount of TKA operations performed in the United States, and with focus on value-based healthcare, it is imperative to understand why total knees fail.