Objective Using manganese enhanced MR imaging(ME-MRI)as a standard to validate the accuracy of white matter diffusion tenor tractography(DTT)with different gradients orientations in macaque monkeys.Methods Seven adult male macaque monkeys were scanned for DTY images with different number of gradients orientations.When all data were acquired.3 μl of 0.8 mol aqueous solution of MnCl2 was injected into the primary motor cortex representing forelimb for ME-MRI scanning 48 hours later.On the images of fractional anisotropy(FA),seed region for fiber tracking was chosen according to the subcortical enhanced range on ME-MRI,then the DTT fiber tracts proiecting on axial images of FA were compared with enhancement region on T1WI of ME-MRI.Results Under the calculation method for fiber tracking in the study,different motion-probing gradients orientations led to results consistent with ME-MRI for the brain above the midbrain level.All group's concordance score of fibertracking results were good.Among them,30 and 64 orientation fiber tracking results were optimal.Below the midbrain level,there was significant difference between DTT fiber tracking and ME-MRI fiber tracking. Conclusion Different motion-probing gradients orientations do not influence DTT fiber tracking.But below the midbrain level.the results of DTT fiber tracking were not reliable according to the standard results of ME-MRI fibe tracking.

Objective:To investigate the status quo of professional identity of nursing undergraduates in Beijing and analyze its influencing factors and to provide basis for carrying out professional identity education of nursing undergraduates.Methods:Using the convenient sampling method, a total of 726 nursing undergraduates from four undergraduate colleges in Beijing from June to September 2020 were selected as research objects. General information questionnaire, Professional Identity Questionnaire for Nurse Students (PIQNS) and Professional Self-efficacy Questionnaire for Nurse Students (PSQNS) were used to investigate them. A total of 726 questionnaires were distributed and 615 valid questionnaires were recovered.Results:The total scores of PIQNS and PSQNS among 615 nursing undergraduates in Beijing were respectively 55.00 (36.00, 66.00) and 86.00 (60.00, 101.00) . There was a positive correlation between PIQNS total score and PSQNS total score of nursing undergraduates ( r=0.928, P<0.01) . The results of multiple linear regression analysis showed that gender, whether there was a class tenure, whether he was an only child, reasons for attending nursing major and whether he had clinical practice or internship experience were the influencing factors of professional identity of nursing undergraduates in Beijing ( P<0.01) , which could explain 17.6% of the total variation. Conclusions:The professional identity of nursing undergraduates in Beijing is at the medium level and still needs to be improved. Nursing educators should pay attention to the emotional and psychological status of nursing undergraduates and take appropriate measures to provide vocational education for nursing undergraduates, so as to further improve their professional identity.

Objective:To explore the current status of cognitive function of the older adults in Beijing,and to analyze the factors affecting their cognitive function.Methods:It was a cross-sectional study.A questionnaire survy was conducted in 2023 among the older adults in Beijing.The cognitive function of the older adults was assessed with the Hong Kong brief cognitive test(HKBC)scale,a simple cognitive assessment tool.Using SPSS 27.0 to perform the descriptive analysis and multiple linear regression analy-sis of factors,which affect cognitive function among the older adults.Results:Totally 349 older adults were recruited,with the highest percentage of respondents aged 60-69 years(41.3％),of whom 58.7％were female,88.0％of the respondents had a junior high school or above education level.Most of the older adults(68.8％)worked 35-48 h/week before they retired,and 14.0％of the older adults had a family history of dementia.After controlling age and gender,the linear regression analysis showed that marital status married(β=0.501,95％CI:0.144-0.859)and 3-4 times physical activity per week(β=0.617,95％CI:0.087-1.148)were protective factors of cognitive function in the older adults,and depressive symptoms were a risk factor(β=-0.723,95％CI:-1.198 to-0.247)of cognitive function for the older adults.Conclusion:In this study,the factors influencing cognitive function among the older adults was analyzed based on a life-cycle perspective.Lack of physical activity and depressive symptoms were risk factors for cognitive function among the older adults.It was suggested that strengthening physical activity,improving mental health of the older adults,as well as conducting preventive intervention in early stages of the life-cycle will be benefit for preventing and slowing cognitive decline in the older adults.