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*** movements in the dark:saccades to non-visual targets

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Annals of Eye Science 2018年第1期 461-461页

作者： Vanessa Harrar William Le Maurice Ptito aarlenne z.khan Laboratoire de la vision de l’attention et de l’action VISATTACUniversitéde MontréalMontréalQCCanada Chaire de recherche Harland Sanders en Sciences de la Vision Universitéde MontréalMontréalQCCanada

Background:Saccades are rapid and abrupt eye movements that allow us to change the point of fixation very *** are generally made to visual points of interest,but we can also saccade to non-visual objects that attract our *** there is a plethora of studies investigating saccadic eye movements to visual targets,there is very little evidence of how eye movement planning occurs when individuals are performing eye movements to non-visual targets across different sensory ***:Fifteen adults with normal,or corrected to normal,vision made saccades to either visual,auditory,tactile or proprioceptive *** the auditory condition a speaker was positioned at one of eight locations along a circle surrounding a central fixation *** the proprioceptive condition the participant’s finger was placed at one of the eight *** the tactile condition participants were touched on their right forearm in one of four eccentric location,left and right of a central *** movements were made in complete ***:We compared the precision and accuracy of the eye movements to tactile,proprioceptive,and auditory targets in the ***,both precision and accuracy of movements to non-visual targets were significantly lower compared to visual ***:These differences emphasize the central role of the visual system in saccade planning.

关键词： Saccades fixation multisensory perceptual shift bias

*** attentional allocation during visual search in the presence of an artificial scotoma in younger and older adults

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Annals of Eye Science 2018年第1期 466-466页

作者： Anne-Sophie Laurin Trang Tran Gunnar Blohm Laure Pisella aarlenne z.khan Department of Neuroscience Universitéde MontréalQCCanada Department of Psychology Universitéde MontréalQCCanada ImpAct Centre de Recherche en Neurosciences de LyonFrance École d’Optométrie Universitéde MontréalQCCanada

Background:Age related macular degeneration(AMD)is one of the main causes of vision loss in older adults,generating,in most cases,a central scotoma that reduces central visual acuity(Noble&Chaudhary,2010).People affected by AMD have to rely on peripheral visual information and would highly benefit from efficiently allocating their attention to the ***,attention can improve peripheral spatial resolution(Carrasco,Ling&Read,2004)and can be allocated to a certain expanse of space outside of the central visual span,known as the attentional *** span has been shown to be decreased in people with AMD with less attention allocated to the periphery and more to the central visual field(Cheong et al.,2008),however it remains unknown whether aging is also a contributing ***:Fourteen healthy younger(mean age=21.8 years,SD=1.5)and 8 older adults(mean age=69.6 years,SD=7.3)performed a pop-out and a serial version of a visual search task,in the presence of different sized gaze-contingent invisible and visible artificial central scotomata(no scotoma,3°diameter,5°and 7°).Participants were asked to indicate as quickly as possible whether a target was present or not among distractors whose number varied(16,32 or 64 objects).We wished to determine whether the size of the scotoma,occluding different degrees of central vision,affected visual search differently for younger *** ***:Both the younger and older participants showed higher reaction times(RTs)to find the target for the serial version(M=2,074 ms for younger adults,M=3,853 ms for older adults)compared to the pop-out version(M=866 ms,M=1,475 ms,Pze on older adults(3°scotoma M=3,276 ms;7°scotoma M=3,877 ms,P<0.05),however,accurate performance was higher wit

关键词： Visual attention scotoma visual search

***-saccadic attentional facilitation is influenced by irrelevant post-saccadic changes

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Annals of Eye Science 2018年第1期 454-454页

作者： Maxime Bleau Anne-Sophie Laurin Anton Malienko Trang Tran Laure Pisella aarlenne z.khan Department of Neuroscience Universitéde MontréalQCCanada Department of Psychology Universitéde MontréalQCCanada École d’Optométrie Universitéde MontréalQCCanada ImpAct Centre de Recherche en Neurosciences de LyonFrance

Background:Many studies have shown that attention is shifted toward the goal of the upcoming *** has been suggested that the purpose of this attentional shift is to aid in trans-saccadic integration by acting as a‘pointer’(Cavanagh,Hunt,Afraz&Rolfs,2010)for remembering,processing and updating objects across saccadic eye movements(Rolfs,Jonikaitis,Deubel&Cavanagh,2011).We tested this hypothesis that pre-saccadic attentional facilitation acts as a pointer for trans-saccadic integration by investigating how irrelevant post-saccadic changes influenced pre-saccadic attentional *** one hand,if pre-saccadic attentional facilitation is an independent process involved only in enhancing peripheral information before the saccade,then manipulating visual information(absence or shift)after the saccade should have no influence on *** the other hand,if pre-saccadic attentional facilitation is involved in trans-saccadic integration,changes in visual information should influence discrimination of the pre-saccadic ***:We tested different conditions involving different post-saccadic *** the baseline condition,participants made a saccade at the appearance of an arrow and discriminated a symbol(DS)that was presented briefly before the saccade at one of six peripheral *** symbol was masked thereafter with a figure 8,which remained till the end of the ***,the DS was always presented while participants were fixating at center,and only the figure 8 was present at the end of the *** were instructed to make the saccade then report the identity of the DS(4AFC).We then tested how blanking post-saccadic information[blanking of the saccade goal(SG)location,DSOff condition;of the entire visual scene including or excluding the SG location,AllOff and DSOnly conditions]and how displacement of the figure 8s after the saccade would affect ***:We observed that discrimination performance was

关键词： Saccadic eye movements trans-saccadic integration

AB061. Changes in eye movement strategies during a discrimination task in the presence of artificial central scotomas

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Annals of Eye Science 2018年第1期 467-467页

作者： Paul Lene Trang Tran Anne-Sophie Laurin Romain Fournet Frédéric Gosselin aarlenne z.khan École d’optométrie Universitéde MontréalMontréalQCCanada Département de Psychologie Universitéde MontréalMontréalQCCanada

Background:The goal of the present research was to study whether the presence of an artificial central scotoma resulted in changes in eye movement strategies over the course of multiple days of *** wished to determine how central vision loss,similar to age macular degeneration(AMD),affects eye movements,specifically the foveal-target *** also wished to determine if an invisible compared to a visible scotoma led to delayed or different strategies,given that AMD patients are mostly unaware of their condition as they are unconscious of the presence of their central ***:Eleven healthy participants(6 females,M=22.18,SD=1.94)were asked to perform a discrimination task,where they responded whether the orientation of an eccentric target(Gabor,10 deg to the left of fixation)was clockwise or *** target was surrounded by four distractor Gabors,thus making discrimination more difficult using peripheral *** target’s orientation varied 10°clockwise to 10°counter-clockwise in 1°*** participant performed four blocks of 75 trials each per day over 10 days,the first day being a baseline as the participant were tested without any *** measured discrimination performance and precision(position of the eye in X and Y).Results:Results showed similar patterns of discrimination reaction time and accuracy as well as changes to eye position for both the visible and the invisible scotoma *** time significantly decreased on the last day of training compared to the first(first day M=2,965 ms,last day M=1,567 ms,Pzontal(X)position of first saccade relative to the target(first=−0.4°,last=−0.13°)but there was a significant upward shift(first=0.08°***=0.58°,P<0.05);participants shifted their eye position on the Y axis so that they were looking at a point slightly above the tar

关键词： Adaptation scotoma vision eye age macular degeneration(AMD) significant results

*** between control of saccadic eye movements and performance in other cognitive tasks in younger adults,older adults and patients with Parkinson’s disease

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Annals of Eye Science 2018年第1期 479-479页

作者： Julie Ouerfelli-Ethier Basma Elsaeid Julie Des Groseilliers Lydia Ouchene Douglas P.Munoz Gunnar Blohm aarlenne z.khan École d'Optométrie Universitéde MontréalMontréalQCCanada Center for Neuroscience Studies Queen's UniversityKingstonONCanada Department of Medicine and Health Sciences Universitéde SherbrookeSherbrookeQCCanada

Background:Cognitive control is defined as the ability to act flexibly in the environment by either behaving automatically or inhibiting said automatic behaviour and it can be measured using an interleaved pro/anti-saccade *** in cognitive control has been attributed to normal aging and neurological illnesses such as Parkinson’s disease(PD)as well as decline in other cognitive *** parallel might highlight the role played by cognitive control in information processing and working ***,little is known about the relationship between cognitive control and other cognitive processes such as visual memory,decision making,and visual *** thus propose to correlate the incidence of impaired cognitive control with deficits in visual memory,decision making and visual search in three groups:younger adults,older adults and patients with idiopathic ***:Seventy-one participants,namely 34 adults(M=22.75,SD=3.8),22 older adults(M=67.4,SD=8.3),and 20 PD patients(M=65.59,SD=8.2)performed four tasks:interleaved pro/anti-saccade,visual memory,decision making,and serial and pop-out visual ***:Results show that within each group,anti-saccade error rate(ER)were significantly and negatively correlated with visual memory ER(ryounger=−0.378,P=0.036;rolder=−0.440,Polder=0.046;rPD=−0.609,P=0.016).On the other hand,correct decision-making reaction times(RT)were significantly correlated with anti-saccade ER,and RTs only in older adults(rER=0.529,P=0.014;rRT=0.512,P=0.018)and PD patients(rER=0.727,P=0.012;rRT=0.769,P=0.001).For visual search,PD patients showed a significant relationship between RTs for correct pro-saccades and pop-out(r=0.665,P=0.007),and serial(r=0.641,P=0.010)search ***,there was a significant correlation between MoCA scores and anti-saccade RTs(r=−0.559,P=0.030)and ER(r=−0.562,P=0.029)in PD *** together,these results support the hypothesis of PD patients’reliance on bottom-up processes as top-down proces

关键词： Saccade cognitive control Parkinson's disease

Precipitation of multi-type nano-quasicrystals in a Mg-zn-Y alloy

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Journal of Magnesium and Alloys 2024年第3期12卷 997-1008页

作者： W.z.Wang X.z.zhou L.F.zhang H.Q.Ye z.Q.Yang Shenyang National Laboratory for Materials Science Institute of Metal ResearchChinese Academy of ScienceShenyang 110016China Ji Hua Laboratory Foshan 528251China Foshan University Foshan 528231China

Mg-6zn-1Y(at.%)ribbons with strengthening precipitates of multi-type nanoquasicrystals were prepared by melt-spinning followed by aging *** evolution of the rapidly solidified ribbons during isothermal aging was comprehensively studied using various electron microscopy *** new kinds of decagonal quasicrystals were formed in aged ribbons,in addition to precipitation of nanometer icosahedral ***-resolution observations reveal that both decagonal quasicrystals can be modeled by quasiperiodic tiling with decagonal clusters of 2.5 nm in diameter,but overlap of neighboring clusters in both decagonal quasicrystals is different from the Gummelt model observed in other quasicrystals.A shell composed of complex Laves Mg-zn domains was formed surrounding each decagonal quasicrystal precipitate upon prolonged *** addition,all kinds of nanoprecipitates exhibit excellent structure and size stability at 573 *** findings may have implications for not only fundamental studies about quasicrystals,but also microstructural manipulation of high-performance Mg alloys.

关键词： Quasicrystal Mg alloys Rapid solidification Scanning-transmission electron microscopy.

On power series statistical convergence and new uniform integrability of double sequences

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Applied Mathematics(A Journal of Chinese Universities) 2024年第3期39卷 519-532页

作者： Sevda Y■ld■z Kamil Demirci Sinop University Department of MathematicsSinopTurkey

In the present paper,we mostly focus on P_(p)^(2)-statistical *** will look into the uniform integrability via the power series method and its characterizations for double ***,the notions of P_(p)^(2)-statistically Cauchy sequence,P_(p)^(2)-statistical boundedness and core for double sequences will be described in addition to these findings.

关键词： power series methods statistical convergence uniform integrability double sequences

Rational design of AgGaS/znS/znS quantum dots with a near-unity photoluminescence quantum yield via double shelling scheme

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Journal of Materials Science & Technology 2024年第2期169卷 235-242页

作者： H.X.Lu H.Liu z.z.Fu Y.Y.Chen H.Q.Dai z.Hu W.L.zhang R.Q.Guo Institute for Electric Light Sources School of Information Science and TechnologyFudan UniversityShanghai 200433China Institute of Future Lighting Academy for Engineering and TechnologyFudan UniversityShanghai 200433China Yiwu Research Institute of Fudan University YiwuZhejiang 322000China zhongshan-Fudan Joint Innovation Center Zhongshan 528437China

In this study,a two-step method was used to synthesize highly luminescent AgGaS/znS/znS quantum dots(QDs).In the first step,an inner znS shell was formed via a one-pot method,which resulted in a smaller lattice mismatch between the AgGaS core and the outer znS shell,thereby facilitating the formation of a thick outer *** the two-step shelling process,the synthesized AgGaS/znS/znS QDs showed an excellent photoluminescence quantum yield(PLQY)of 96.4%with a peak wavelength of 508 nm,repre-senting the highest PLQY reported thus far for AgGaS ***,the effect of halogen ions in zn precursors on the shelling process was *** was proposed that the capacity of halogen ions to coordinate with the QDs influenced the balance between zn cation diffusion and znS shelling ***,the znS shelling reaction was dominant when znCl_(2)was employed,while zn cation diffusion was the dominant process under the I^(−)-rich *** work provides insights into the interfacial restructuring during the znS shelling and offers a clear map for the tailored synthesis of core/shell QDs.

关键词： AgGaS Quantum dots Photoluminescence Core/shell Alloyed core/shell interface

Importance of diet and intestinal microbiota in the prevention of colorectal cancer-colonoscopy early screening diagnosis

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World Journal of Gastrointestinal Oncology 2024年第8期16卷 3428-3435页

作者： Miljana z Jovandaric Department of Neonatology Clinic for Gynecology and ObstetricsUniversity Clinical Center of SerbiaBelgrade 11070Serbia

Colorectal cancer is a term used to describe colon and rectal cancer,which is the third most common type of cancer.A MEDLINE and PubMed search resulted in the inclusion of manuscripts written in the last 10 years,using keywords relevant to the topic of the *** analyzing the aim of the searched studies and manuscripts,adequate articles were included that described the stated *** frequency of colorectal cancer varies with climate,nutrition,and many other factors,primarily endogenous,hereditary,intestinal microbiome,as well as external factors,such as exposure of the individual to stress,and bad eating *** cancer and rectal cancer or colorectal cancer in general in the early stages of the disease,may not show symptoms or are barely *** cancer symptoms will most often not develop until the disease has progressed to stage 2 or *** screening tests for colon or rectal cancer,especially colonoscopy,are recommended as part of a regular checkup for people aged 50 years or younger who are at high risk due to a family history of the disease or other *** and colonoscopy as an early screening method play an important role in the prevention of colorectal cancer.

关键词： Colorectal cancer Causes Symptoms Screening Diet and colonoscopy