Tissue homeostasis requires a carefully-orchestrated balance between cell proliferation, cellular senescence and cell death. Cells proliferate through a cell cycle that is tightly regulated by cyclin-dependent kinase ...Tissue homeostasis requires a carefully-orchestrated balance between cell proliferation, cellular senescence and cell death. Cells proliferate through a cell cycle that is tightly regulated by cyclin-dependent kinase activities. Cellular senescence is a safeguard program limiting the proliferative competence of cells in living organisms. Apoptosis eliminates unwanted cells by the coordinated activity of gene products that regulate and effect cell death. The intimate link between the cell cycle, cellular senes- cence, apoptosis regulation, cancer development and tumor responses to cancer treatment has become eminently apparent. Extensive research on tumor suppressor genes, oncogenes, the cell cycle and apoptosis regulatory genes has revealed how the DNA damage-sensing and -signaling pathways, referred to as the DNA-damage response network, are tied to cell proliferation, cell-cycle arrest, cellular senescence and apoptosis. DNA-damage responses are complex, involving “sensor” proteins that sense the damage, and transmit signals to “transducer” proteins, which, in turn, convey the signals to numerous “effector” proteins implicated in specific cellular pathways, including DNA repair mechanisms, cell-cycle checkpoints, cellular senescence and apoptosis. The Bcl-2 family of proteins stands among the most crucial regulators of apoptosis and performs vital functions in deciding whether a cell will live or die after cancer chemotherapy and irradiation. In addition, several studies have now revealed that members of the Bcl-2 family also interface with the cell cycle, DNA repair/recombination and cellular senescence, effects that are generally distinct from their function in apoptosis. In this review, we report progress in understanding the molecular networks that regulate cell-cycle checkpoints, cellular senescence and apoptosis after DNA damage, and discuss the influence of some Bcl-2 family members on cell-cycle checkpoint regulation.展开更多
Highly Resonant Power Transfer (HRPT) technology is currently receiving very significant attention from the industry and the smart power grid distribution community in particular. This technology ensures electrical po...Highly Resonant Power Transfer (HRPT) technology is currently receiving very significant attention from the industry and the smart power grid distribution community in particular. This technology ensures electrical power transmission between two points while controlling the level of transmitted power and ensures the immediate shutdown of the transmitted power in the event of a problem. This paper reviews the inductive power transfer method and describes the design of an ultra-compact PLA core electromagnetic coupler. The proposed architecture confines the magnetic field in a toroidal PLA core transformer, and by avoiding the use of heavy and bulky shielding plates, reduces magnetic losses and avoids the Curie point. As a result, the overall unit has a weight of 5 kg and a volume of only 0.013 m<sup>3</sup>. The electromagnetic coupler is capable of transferring a peak power of 150 kW with an operating frequency of 193 kHz, giving a satisfactory efficiency of 95%. The proposed novel system was first investigated through CST 3D numerical modelling to determine the electrical parameters of the coupler’s equivalent circuit and its efficiency, to verify its compatibility with the ICNIRP 2010 standard and to evaluate its temperature rise with an air-cooling system. Afterwards, the designed coupler was built with a 3D printing device and finally tested experimentally. Simulation and experimental results are compared and show a good agreement.展开更多
Objective: This study was conducted to investigate and compare the coordinatio n and stabilization of axial segments during walking with and without horizontal voluntary head turns, in healthy (n=5) and hemiparetic (n...Objective: This study was conducted to investigate and compare the coordinatio n and stabilization of axial segments during walking with and without horizontal voluntary head turns, in healthy (n=5) and hemiparetic (n=10) subjects. Methods : Subjects were instructed to turn the head as fast and as soon as possible in t he direction indicated by an illuminated arrow signal(right, left or none) that was triggered at initial contact of the right (healthy) or paretic (hemiparetic) foot. Head, thorax,and pelvis motions were obtained from a 9-segment model usi ng retro-reflective markers and a Vicon-512 system with 6 high-resolution cam eras. Coordination of axial segments in the horizontal plane was characterized u sing cyclographs and cross-correlat- ion analyses. Stabilization of the segments was quantified using root mean squ are (RMS) values of the segment’s normalized acceleration profile. Results: The healthy subjects showed a direction-dependent modulation of axial segment coor dination, with head turns toward and away from the stance limb favoring and hind ering, respectively, the contrarotational pattern of the thorax with respect to the pelvis during locomotion. Meanwhile, pelvis motions remained unaltered.This direction-specific modulation pattern was disrupted in the hemiparetic subjects , both in the spatial and temporal domains.Moreover, larger RMS values for head and thorax segments were observed in the hemiparetic groups, both with and witho ut the superimposition of voluntary head motions. Conclusions:The findings sugge st that: (1) head rotations during walking modify axial segment coordination in a direction-specific manner, (2) the pelvic rotations associated with locomotio n remained unaffected by head rotations and (3) stroke alters this coordination behavior, which may contribute to balance dysfunctions during locomotion.展开更多
Introduction:The world’s population is rapidly aging.Unregulated health care workers(UH-CWs)are emerging as a potentially important workforce in the care of older adults.Objective:A review was conducted to identify t...Introduction:The world’s population is rapidly aging.Unregulated health care workers(UH-CWs)are emerging as a potentially important workforce in the care of older adults.Objective:A review was conducted to identify the activities of UHCWs with respect to con-tributions and limitations.Methods:A systematic integrative literature review was conducted using online databases(LILACS,PubMed,EMBASE,CINAHL,and grey literature).The inclusion criteria were as fol-lows:(i)description of UHCW activities related to older adults;and(ii)description of UHCW activities performed in Brazil or Canada.Results:Eleven papers were included in this review.In both countries,UHCW activities included health promotion,mental health care,and rehabilitation.In Brazil,UHCWs performed integrated care,while in Canada UHCWs performed personal care and housekeeping.Conclusion:These results highlight the potential and limits of UHCWs who provide care for the aging population.Such information is important to health and social policy making and household decision making.展开更多
In this paper, a novel unified plasticity methodology is proposed to allow the coupling of rate-and temperature-sensitivity of engineering alloys as well as the non-linear kinematic hardening behavior often observed d...In this paper, a novel unified plasticity methodology is proposed to allow the coupling of rate-and temperature-sensitivity of engineering alloys as well as the non-linear kinematic hardening behavior often observed during cyclic loading. The proposed methodology is general in the sense that an arbitrary constitutive model may be chosen for the viscoplastic part, as well as the cyclic part. We adapt our model with a physically-motivated viscoplasticity flow rule and a nonlinear kinematic hardening model. In contrast with other unified plasticity models, the simplified theory involves few material parameters that can be readily calibrated from standard mechanical tests. The capabilities of the proposed theory are demonstrated for a hot rolled annealed 304 L stainless steel supplied by Vimetal Peckover. The model is tested with stress–strain curves obtained from standard tensile and cyclic uniaxial tests at various strain amplitudes and strain-rates, and good accuracy of the response is obtained for strains up to 15%, within a temperature range of 293–673 K. We note that the cyclic plasticity model in our adapted theory can be readily enhanced with ratchetting, mean stress relaxation, strain amplitude history, Masing effects or other complex capabilities.展开更多
基金the Canadian Institutes of Health Research and the Cancer Research Society, and fellowships by the Health Research Funds of Quebec, Canada
文摘Tissue homeostasis requires a carefully-orchestrated balance between cell proliferation, cellular senescence and cell death. Cells proliferate through a cell cycle that is tightly regulated by cyclin-dependent kinase activities. Cellular senescence is a safeguard program limiting the proliferative competence of cells in living organisms. Apoptosis eliminates unwanted cells by the coordinated activity of gene products that regulate and effect cell death. The intimate link between the cell cycle, cellular senes- cence, apoptosis regulation, cancer development and tumor responses to cancer treatment has become eminently apparent. Extensive research on tumor suppressor genes, oncogenes, the cell cycle and apoptosis regulatory genes has revealed how the DNA damage-sensing and -signaling pathways, referred to as the DNA-damage response network, are tied to cell proliferation, cell-cycle arrest, cellular senescence and apoptosis. DNA-damage responses are complex, involving “sensor” proteins that sense the damage, and transmit signals to “transducer” proteins, which, in turn, convey the signals to numerous “effector” proteins implicated in specific cellular pathways, including DNA repair mechanisms, cell-cycle checkpoints, cellular senescence and apoptosis. The Bcl-2 family of proteins stands among the most crucial regulators of apoptosis and performs vital functions in deciding whether a cell will live or die after cancer chemotherapy and irradiation. In addition, several studies have now revealed that members of the Bcl-2 family also interface with the cell cycle, DNA repair/recombination and cellular senescence, effects that are generally distinct from their function in apoptosis. In this review, we report progress in understanding the molecular networks that regulate cell-cycle checkpoints, cellular senescence and apoptosis after DNA damage, and discuss the influence of some Bcl-2 family members on cell-cycle checkpoint regulation.
文摘Highly Resonant Power Transfer (HRPT) technology is currently receiving very significant attention from the industry and the smart power grid distribution community in particular. This technology ensures electrical power transmission between two points while controlling the level of transmitted power and ensures the immediate shutdown of the transmitted power in the event of a problem. This paper reviews the inductive power transfer method and describes the design of an ultra-compact PLA core electromagnetic coupler. The proposed architecture confines the magnetic field in a toroidal PLA core transformer, and by avoiding the use of heavy and bulky shielding plates, reduces magnetic losses and avoids the Curie point. As a result, the overall unit has a weight of 5 kg and a volume of only 0.013 m<sup>3</sup>. The electromagnetic coupler is capable of transferring a peak power of 150 kW with an operating frequency of 193 kHz, giving a satisfactory efficiency of 95%. The proposed novel system was first investigated through CST 3D numerical modelling to determine the electrical parameters of the coupler’s equivalent circuit and its efficiency, to verify its compatibility with the ICNIRP 2010 standard and to evaluate its temperature rise with an air-cooling system. Afterwards, the designed coupler was built with a 3D printing device and finally tested experimentally. Simulation and experimental results are compared and show a good agreement.
文摘Objective: This study was conducted to investigate and compare the coordinatio n and stabilization of axial segments during walking with and without horizontal voluntary head turns, in healthy (n=5) and hemiparetic (n=10) subjects. Methods : Subjects were instructed to turn the head as fast and as soon as possible in t he direction indicated by an illuminated arrow signal(right, left or none) that was triggered at initial contact of the right (healthy) or paretic (hemiparetic) foot. Head, thorax,and pelvis motions were obtained from a 9-segment model usi ng retro-reflective markers and a Vicon-512 system with 6 high-resolution cam eras. Coordination of axial segments in the horizontal plane was characterized u sing cyclographs and cross-correlat- ion analyses. Stabilization of the segments was quantified using root mean squ are (RMS) values of the segment’s normalized acceleration profile. Results: The healthy subjects showed a direction-dependent modulation of axial segment coor dination, with head turns toward and away from the stance limb favoring and hind ering, respectively, the contrarotational pattern of the thorax with respect to the pelvis during locomotion. Meanwhile, pelvis motions remained unaltered.This direction-specific modulation pattern was disrupted in the hemiparetic subjects , both in the spatial and temporal domains.Moreover, larger RMS values for head and thorax segments were observed in the hemiparetic groups, both with and witho ut the superimposition of voluntary head motions. Conclusions:The findings sugge st that: (1) head rotations during walking modify axial segment coordination in a direction-specific manner, (2) the pelvic rotations associated with locomotio n remained unaffected by head rotations and (3) stroke alters this coordination behavior, which may contribute to balance dysfunctions during locomotion.
文摘Introduction:The world’s population is rapidly aging.Unregulated health care workers(UH-CWs)are emerging as a potentially important workforce in the care of older adults.Objective:A review was conducted to identify the activities of UHCWs with respect to con-tributions and limitations.Methods:A systematic integrative literature review was conducted using online databases(LILACS,PubMed,EMBASE,CINAHL,and grey literature).The inclusion criteria were as fol-lows:(i)description of UHCW activities related to older adults;and(ii)description of UHCW activities performed in Brazil or Canada.Results:Eleven papers were included in this review.In both countries,UHCW activities included health promotion,mental health care,and rehabilitation.In Brazil,UHCWs performed integrated care,while in Canada UHCWs performed personal care and housekeeping.Conclusion:These results highlight the potential and limits of UHCWs who provide care for the aging population.Such information is important to health and social policy making and household decision making.
文摘In this paper, a novel unified plasticity methodology is proposed to allow the coupling of rate-and temperature-sensitivity of engineering alloys as well as the non-linear kinematic hardening behavior often observed during cyclic loading. The proposed methodology is general in the sense that an arbitrary constitutive model may be chosen for the viscoplastic part, as well as the cyclic part. We adapt our model with a physically-motivated viscoplasticity flow rule and a nonlinear kinematic hardening model. In contrast with other unified plasticity models, the simplified theory involves few material parameters that can be readily calibrated from standard mechanical tests. The capabilities of the proposed theory are demonstrated for a hot rolled annealed 304 L stainless steel supplied by Vimetal Peckover. The model is tested with stress–strain curves obtained from standard tensile and cyclic uniaxial tests at various strain amplitudes and strain-rates, and good accuracy of the response is obtained for strains up to 15%, within a temperature range of 293–673 K. We note that the cyclic plasticity model in our adapted theory can be readily enhanced with ratchetting, mean stress relaxation, strain amplitude history, Masing effects or other complex capabilities.
