Historical overview In 1975,Michel Mathieu became the head of the newly autonomous Department of Ophthalmology at the University of Montreal.Mathieu’s growing reputation as a skilled clinician and researcher attracte...Historical overview In 1975,Michel Mathieu became the head of the newly autonomous Department of Ophthalmology at the University of Montreal.Mathieu’s growing reputation as a skilled clinician and researcher attracted excellent candidates to the department(1).Under his direction,Suzanne Véronneau-Troutman became the first resident and,subsequently,the first female ophthalmic surgeon at University of Montreal.Her immense contribution to the field of strabismus later gained worldwide appreciation,as recognized by the annual American Academy of Ophthalmology award named after her(2).Mathieu’s work,and that of his recruits,led to major advances in the fields of corneal transplantation,retinal degenerations,electroretinography,and ophthalmic surgical instrumentation(3).展开更多
Background:Cognitive assessments,such as the Montreal Cognitive Assessment(MoCA),use components that assume intact sensory abilities,however,adults show concomitant decreases in visual acuity with increasing age.Score...Background:Cognitive assessments,such as the Montreal Cognitive Assessment(MoCA),use components that assume intact sensory abilities,however,adults show concomitant decreases in visual acuity with increasing age.Scores on cognitive assessments are typically lower for individuals with visual impairments compared to individuals with normal/corrected to normal vision.But it is not clear if lowers scores on cognitive assessments are due to the assessments relying on visual stimuli,or if individuals with visual impairments are actually more likely to have cognitive impairments.Therefore we simulated visual impairments,i.e.,reduced visual acuity and contrast sensitivity,in young healthy adults to determine how this impacts their scores on a measure of cognitive ability,i.e.,the MoCA.Methods:Participants(n=19)completed one of the three version of the MoCA under three conditions(20/20,simulated 20/80,simulated 20/200).The MoCA was administered following the clinical protocols.Only participants that scored>26(i.e.,normal cognitive function)at 20/20 were included in the analysis.For comparison,we included MoCA data from a sample of older adults with normal vision(n=19,Mage=74,Acuity M=0.04 logMAR,SD=0.16)or visual impairment(n=19,Mage=79,Acuity M=0.35 logMAR,SD=0.3).Results:Acuity of participants at 20/20(M=0.06 LogMAR,SD=0.1),simulated 20/80(M=0.63,SD=0.18)and simulated 20/200(M=0.88,SD=0.19)showed that the participants experienced simulated acuity loss with the goggles.For the MoCA scores,we found a main effect of acuity(F=16.22,P<0.001,η2=0.375,BF10=5,618).Planned post hoc comparisons showed a significant difference between scores with a 20/20 acuity(M=27.26,SD=0.93)and 20/80(M=24.74,SD=1.66,t=5.62,ptukey<0.001,d=1.88),and between 20/20 and 20/200(M=25.63,SD=1.46,t=3.63,ptukey=0.002,Cohen’s d=1.33).However,no difference was observed between 20/80 and 20/200(t=−1.99,ptukey=0.125,d=0.572).The MoCA scores in older adults with normal vision(M=27.32,SD=2.41)and with visual impairment(M=26.68,SD=2.52),did not differ significantly(t36=−0.787,P=0.436,d=0.26,BF10=0.4).Conclusions:Our findings show that simulated reductions in visual acuity and contrast sensitivity lead to lower scores on measures of cognitive ability,specifically the MoCA.However,it appears that older adults with actual visual impairments may have developed compensatory strategies to adapt to this loss in visual acuity as there were no significant differences in scores of older adults with and without visual impairments.Therefore,we would recommend that when assessing an individual with visual impairments to conduct the cognitive test by re-scoring it without the visual components,e.g.,the MoCA Blind,to magnify the visual components,or to substitue the visual component when possible using auditory alternatives,e.g.,the oral trail making task.展开更多
Alternative technologies have emerged to reduce the greenhouse gas (GHG) emissions of traditional commuter rail systems powered by diesel. Even larger reductions can be obtained with energy production from renewable r...Alternative technologies have emerged to reduce the greenhouse gas (GHG) emissions of traditional commuter rail systems powered by diesel. Even larger reductions can be obtained with energy production from renewable resources. This paper uses the commuter rail system in Montreal, Quebec, as a case study for implementing alternative technologies, namely, complete electrification of the network (only one of the existing five lines is electrified) and hydrogen fuel cell-powered trains. It is important to note that the main source of electricity generation in Quebec is hydropower which is offered at a relatively low cost. Several criteria were considered to determine the most suitable alternative including GHG emissions from operation and fuel production, operation and capital costs, and technological and commercial viability. Electrification of the commuter rail system would decrease annual emissions by 98% which is more than 27,000 tons. The GHG reductions for hydrogen trains are lower than electric trains but still substantial. The operation costs favor the electrification scenario;however, the high costs of electrical infrastructure make hydrogen trains more competitive since additional infrastructure is unnecessary. However, hydrogen trains remain a new and unproven technology;uncertainties associated with it should be settled before full implementation.展开更多
This review comprehensively summarized the potential of artificial intelligence(AI)in the management of esophageal cancer.It highlighted the significance of AI-assisted endoscopy in Japan where endoscopy is central to...This review comprehensively summarized the potential of artificial intelligence(AI)in the management of esophageal cancer.It highlighted the significance of AI-assisted endoscopy in Japan where endoscopy is central to both screening and diagnosis.For the clinical adaptation of AI,several challenges remain for its effective translation.The establishment of high-quality clinical databases,such as the National Clinical Database and Japan Endoscopy Database in Japan,which covers almost all cases of esophageal cancer,is essential for validating multimodal AI models.This requires rigorous external validation using diverse datasets,including those from different endoscope manufacturers and image qualities.Furthermore,endoscopists’skills significantly affect diagnostic accuracy,suggesting that AI should serve as a supportive tool rather than a replacement.Addressing these challenges,along with country-specific legal and ethical considerations,will facilitate the successful integration of multimodal AI into the management of esophageal cancer,particularly in endoscopic diagnosis,and contribute to improved patient outcomes.Although this review focused on Japan as a case study,the challenges and solutions described are broadly applicable to other high-incidence regions.展开更多
Dendritic spines are small protrusions along dendrites that contain most of the excitatory synapses in principal neurons,playing a crucial role in neuronal function by creating a compartmentalized environment for sign...Dendritic spines are small protrusions along dendrites that contain most of the excitatory synapses in principal neurons,playing a crucial role in neuronal function by creating a compartmentalized environment for signal transduction.The plasticity of spine morphologies provides a tunable handle to regulate calcium signal dynamics,allowing rapid regulation of protein expression necessary to establish and maintain synapses(Cornejo et al.,2022).If excitatory inputs were to be located primarily on dendritic shafts,dendrites would frequently short-circuit,preventing voltage signals from propagating(Cornejo et al.,2022).It is thus not surprising that the structural plasticity of dendritic spines is closely linked to synaptic plasticity and memory formation(Berry and Nedivi,2017).While comprehensive in vitro studies have been conducted,in vivo studies that directly tackle the mechanism of dendritic transport and translation in regulating spine plasticity spatiotemporally are limited.展开更多
科学论文被专利技术引用是论文产生技术影响的表征,然而,目前对什么样的科学论文更容易产生技术影响以及影响程度尚不清晰。相比于外部影响因素的不确定性,论文自产出后,其自身知识特性就已确定不变。因此,本文从知识的继承和创新视角出...科学论文被专利技术引用是论文产生技术影响的表征,然而,目前对什么样的科学论文更容易产生技术影响以及影响程度尚不清晰。相比于外部影响因素的不确定性,论文自产出后,其自身知识特性就已确定不变。因此,本文从知识的继承和创新视角出发,选择2000—2009年Web of Science数据库的论文和2000—2020年USPTO(Unit‐ed States Patent andTrademark Office)数据库的专利,基于知识来源将知识特性分为跨学科性和内容创新性,探究知识特性是否有助于论文产生技术影响,在此基础上,进一步分析其对技术影响程度(强度、广度、速度)的作用。研究发现,学科多样性较丰富、均衡性和差异性较低,以及内容创新度较高的论文相对更容易产生技术影响。在产生技术影响的论文中,各维度的跨学科性与技术影响强度、广度和速度均呈现非线性关系;内容创新度相对较低的论文倾向于产生的技术影响强度更大、影响范围更广、影响速度更快。最后,当论文创新水平不同时,学科多样性、均衡性和差异性对技术影响速度的作用差异较为明显,而跨学科综合指标对技术影响强度和广度的作用差异较为明显。展开更多
Mature oligodendrocytes form myelin sheaths that are crucial for the insulation of axons and efficient signal transmission in the central nervous system.Recent evidence has challenged the classical view of the functio...Mature oligodendrocytes form myelin sheaths that are crucial for the insulation of axons and efficient signal transmission in the central nervous system.Recent evidence has challenged the classical view of the functionally static mature oligodendrocyte and revealed a gamut of dynamic functions such as the ability to modulate neuronal circuitry and provide metabolic support to axons.Despite the recognition of potential heterogeneity in mature oligodendrocyte function,a comprehensive summary of mature oligodendrocyte diversity is lacking.We delve into early 20th-century studies by Robertson and Río-Hortega that laid the foundation for the modern identification of regional and morphological heterogeneity in mature oligodendrocytes.Indeed,recent morphologic and functional studies call into question the long-assumed homogeneity of mature oligodendrocyte function through the identification of distinct subtypes with varying myelination preferences.Furthermore,modern molecular investigations,employing techniques such as single cell/nucleus RNA sequencing,consistently unveil at least six mature oligodendrocyte subpopulations in the human central nervous system that are highly transcriptomically diverse and vary with central nervous system region.Age and disease related mature oligodendrocyte variation denotes the impact of pathological conditions such as multiple sclerosis,Alzheimer's disease,and psychiatric disorders.Nevertheless,caution is warranted when subclassifying mature oligodendrocytes because of the simplification needed to make conclusions about cell identity from temporally confined investigations.Future studies leveraging advanced techniques like spatial transcriptomics and single-cell proteomics promise a more nuanced understanding of mature oligodendrocyte heterogeneity.Such research avenues that precisely evaluate mature oligodendrocyte heterogeneity with care to understand the mitigating influence of species,sex,central nervous system region,age,and disease,hold promise for the development of therapeutic interventions targeting varied central nervous system pathology.展开更多
文摘Historical overview In 1975,Michel Mathieu became the head of the newly autonomous Department of Ophthalmology at the University of Montreal.Mathieu’s growing reputation as a skilled clinician and researcher attracted excellent candidates to the department(1).Under his direction,Suzanne Véronneau-Troutman became the first resident and,subsequently,the first female ophthalmic surgeon at University of Montreal.Her immense contribution to the field of strabismus later gained worldwide appreciation,as recognized by the annual American Academy of Ophthalmology award named after her(2).Mathieu’s work,and that of his recruits,led to major advances in the fields of corneal transplantation,retinal degenerations,electroretinography,and ophthalmic surgical instrumentation(3).
文摘Background:Cognitive assessments,such as the Montreal Cognitive Assessment(MoCA),use components that assume intact sensory abilities,however,adults show concomitant decreases in visual acuity with increasing age.Scores on cognitive assessments are typically lower for individuals with visual impairments compared to individuals with normal/corrected to normal vision.But it is not clear if lowers scores on cognitive assessments are due to the assessments relying on visual stimuli,or if individuals with visual impairments are actually more likely to have cognitive impairments.Therefore we simulated visual impairments,i.e.,reduced visual acuity and contrast sensitivity,in young healthy adults to determine how this impacts their scores on a measure of cognitive ability,i.e.,the MoCA.Methods:Participants(n=19)completed one of the three version of the MoCA under three conditions(20/20,simulated 20/80,simulated 20/200).The MoCA was administered following the clinical protocols.Only participants that scored>26(i.e.,normal cognitive function)at 20/20 were included in the analysis.For comparison,we included MoCA data from a sample of older adults with normal vision(n=19,Mage=74,Acuity M=0.04 logMAR,SD=0.16)or visual impairment(n=19,Mage=79,Acuity M=0.35 logMAR,SD=0.3).Results:Acuity of participants at 20/20(M=0.06 LogMAR,SD=0.1),simulated 20/80(M=0.63,SD=0.18)and simulated 20/200(M=0.88,SD=0.19)showed that the participants experienced simulated acuity loss with the goggles.For the MoCA scores,we found a main effect of acuity(F=16.22,P<0.001,η2=0.375,BF10=5,618).Planned post hoc comparisons showed a significant difference between scores with a 20/20 acuity(M=27.26,SD=0.93)and 20/80(M=24.74,SD=1.66,t=5.62,ptukey<0.001,d=1.88),and between 20/20 and 20/200(M=25.63,SD=1.46,t=3.63,ptukey=0.002,Cohen’s d=1.33).However,no difference was observed between 20/80 and 20/200(t=−1.99,ptukey=0.125,d=0.572).The MoCA scores in older adults with normal vision(M=27.32,SD=2.41)and with visual impairment(M=26.68,SD=2.52),did not differ significantly(t36=−0.787,P=0.436,d=0.26,BF10=0.4).Conclusions:Our findings show that simulated reductions in visual acuity and contrast sensitivity lead to lower scores on measures of cognitive ability,specifically the MoCA.However,it appears that older adults with actual visual impairments may have developed compensatory strategies to adapt to this loss in visual acuity as there were no significant differences in scores of older adults with and without visual impairments.Therefore,we would recommend that when assessing an individual with visual impairments to conduct the cognitive test by re-scoring it without the visual components,e.g.,the MoCA Blind,to magnify the visual components,or to substitue the visual component when possible using auditory alternatives,e.g.,the oral trail making task.
文摘Alternative technologies have emerged to reduce the greenhouse gas (GHG) emissions of traditional commuter rail systems powered by diesel. Even larger reductions can be obtained with energy production from renewable resources. This paper uses the commuter rail system in Montreal, Quebec, as a case study for implementing alternative technologies, namely, complete electrification of the network (only one of the existing five lines is electrified) and hydrogen fuel cell-powered trains. It is important to note that the main source of electricity generation in Quebec is hydropower which is offered at a relatively low cost. Several criteria were considered to determine the most suitable alternative including GHG emissions from operation and fuel production, operation and capital costs, and technological and commercial viability. Electrification of the commuter rail system would decrease annual emissions by 98% which is more than 27,000 tons. The GHG reductions for hydrogen trains are lower than electric trains but still substantial. The operation costs favor the electrification scenario;however, the high costs of electrical infrastructure make hydrogen trains more competitive since additional infrastructure is unnecessary. However, hydrogen trains remain a new and unproven technology;uncertainties associated with it should be settled before full implementation.
基金Supported by Japan Society for the Promotion of Science,No.24K11935.
文摘This review comprehensively summarized the potential of artificial intelligence(AI)in the management of esophageal cancer.It highlighted the significance of AI-assisted endoscopy in Japan where endoscopy is central to both screening and diagnosis.For the clinical adaptation of AI,several challenges remain for its effective translation.The establishment of high-quality clinical databases,such as the National Clinical Database and Japan Endoscopy Database in Japan,which covers almost all cases of esophageal cancer,is essential for validating multimodal AI models.This requires rigorous external validation using diverse datasets,including those from different endoscope manufacturers and image qualities.Furthermore,endoscopists’skills significantly affect diagnostic accuracy,suggesting that AI should serve as a supportive tool rather than a replacement.Addressing these challenges,along with country-specific legal and ethical considerations,will facilitate the successful integration of multimodal AI into the management of esophageal cancer,particularly in endoscopic diagnosis,and contribute to improved patient outcomes.Although this review focused on Japan as a case study,the challenges and solutions described are broadly applicable to other high-incidence regions.
基金supported by the National Natural Science Foundation of China(NSFC/RGC/JRF N_HKU735/21)Research Grant Council of Hong Kong,China(17102120,17108821,17103922,C1024-22GF,C7074-21G)+1 种基金Health and Medical Research Fund(HMRF 09200966)(to CSWL)FRQS Postdoctoral Fellowship(to AHKF).
文摘Dendritic spines are small protrusions along dendrites that contain most of the excitatory synapses in principal neurons,playing a crucial role in neuronal function by creating a compartmentalized environment for signal transduction.The plasticity of spine morphologies provides a tunable handle to regulate calcium signal dynamics,allowing rapid regulation of protein expression necessary to establish and maintain synapses(Cornejo et al.,2022).If excitatory inputs were to be located primarily on dendritic shafts,dendrites would frequently short-circuit,preventing voltage signals from propagating(Cornejo et al.,2022).It is thus not surprising that the structural plasticity of dendritic spines is closely linked to synaptic plasticity and memory formation(Berry and Nedivi,2017).While comprehensive in vitro studies have been conducted,in vivo studies that directly tackle the mechanism of dendritic transport and translation in regulating spine plasticity spatiotemporally are limited.
文摘科学论文被专利技术引用是论文产生技术影响的表征,然而,目前对什么样的科学论文更容易产生技术影响以及影响程度尚不清晰。相比于外部影响因素的不确定性,论文自产出后,其自身知识特性就已确定不变。因此,本文从知识的继承和创新视角出发,选择2000—2009年Web of Science数据库的论文和2000—2020年USPTO(Unit‐ed States Patent andTrademark Office)数据库的专利,基于知识来源将知识特性分为跨学科性和内容创新性,探究知识特性是否有助于论文产生技术影响,在此基础上,进一步分析其对技术影响程度(强度、广度、速度)的作用。研究发现,学科多样性较丰富、均衡性和差异性较低,以及内容创新度较高的论文相对更容易产生技术影响。在产生技术影响的论文中,各维度的跨学科性与技术影响强度、广度和速度均呈现非线性关系;内容创新度相对较低的论文倾向于产生的技术影响强度更大、影响范围更广、影响速度更快。最后,当论文创新水平不同时,学科多样性、均衡性和差异性对技术影响速度的作用差异较为明显,而跨学科综合指标对技术影响强度和广度的作用差异较为明显。
基金supported by a grant from the Progressive MS Alliance(BRAVE in MS)Le Grand Portage Fund。
文摘Mature oligodendrocytes form myelin sheaths that are crucial for the insulation of axons and efficient signal transmission in the central nervous system.Recent evidence has challenged the classical view of the functionally static mature oligodendrocyte and revealed a gamut of dynamic functions such as the ability to modulate neuronal circuitry and provide metabolic support to axons.Despite the recognition of potential heterogeneity in mature oligodendrocyte function,a comprehensive summary of mature oligodendrocyte diversity is lacking.We delve into early 20th-century studies by Robertson and Río-Hortega that laid the foundation for the modern identification of regional and morphological heterogeneity in mature oligodendrocytes.Indeed,recent morphologic and functional studies call into question the long-assumed homogeneity of mature oligodendrocyte function through the identification of distinct subtypes with varying myelination preferences.Furthermore,modern molecular investigations,employing techniques such as single cell/nucleus RNA sequencing,consistently unveil at least six mature oligodendrocyte subpopulations in the human central nervous system that are highly transcriptomically diverse and vary with central nervous system region.Age and disease related mature oligodendrocyte variation denotes the impact of pathological conditions such as multiple sclerosis,Alzheimer's disease,and psychiatric disorders.Nevertheless,caution is warranted when subclassifying mature oligodendrocytes because of the simplification needed to make conclusions about cell identity from temporally confined investigations.Future studies leveraging advanced techniques like spatial transcriptomics and single-cell proteomics promise a more nuanced understanding of mature oligodendrocyte heterogeneity.Such research avenues that precisely evaluate mature oligodendrocyte heterogeneity with care to understand the mitigating influence of species,sex,central nervous system region,age,and disease,hold promise for the development of therapeutic interventions targeting varied central nervous system pathology.
