Objective To investigate the effect of single osteochondral defect of the knee on pressure distributions in weight-bearing area of the medial femoral condyle,and further evaluate changes of the location of peak pressure on the medial condyle with the defect size changing.Methods Ten fresh porcine knee joints were fixed in extension position.First,mechanical loads were applied to the medial compartment of the normal porcine knee joint to determine the maximum contact pressure area.Then,rounded osteochondral defects with different diameters(in depth of 9 mm)were drilled at this area,respectively.The 100,200,300 N axial compression loads were applied to the medial compartment of each knee joint,and the strength and location of the peak contact pressure during loading were recorded.Results The peak pressure increased with defect size increasing,and the phenomenon of stress concentration appeared.The peak pressure was significantly higher in the defect with diameter exceeding 8 mm than that in the non-defect knee.The peak pressure showed a similar tendency to move closer to the defect rim as the defect size increased(the distance between the peak pressure position and the defect rim,namely peak-to-rim distance,decreased).Conclusions In the single knee osteochondral defect model,when the diameter of the defect at the weight-bearing area was larger than 8 mm,the peak pressure on the uninjured site significantly increased,and the peak-to-rim distance significantly decreased,which implied 8 mm as a potential threshold for surgical intervention.

Objective To investigate the differences in cortical activation and functional connectivity during speech under different cognitive loads in young individuals.Methods Twenty-one participants(mean age 21.9±1.33 years)were instructed to read short sentences embedded with color words under both congruent(where the color words matched the font color)and incongruent(where the color words did not match the font color)condi-tions.The color words required reading the font color instead of the word itself.Functional near-infrared spectros-copy(fNIRS)was utilized to analyze differences in cortical activation(changes in HbO concentration)and functional connectivity(Pearson correlation of HbO between brain regions)in the dorsolateral prefrontal cortex(DLPFC)and supplementary motor area(SMA)bilaterally.Results The fNIRS results revealed significant increase in HbO con-centration changes in the RDLPFC(t=3.4,P=0.003),LDLPFC(t=2.58,P=0.019),RSMA(t=3.59,P=0.002),and LSMA(t=4.06,P=0.001)under the incongruent condition compared to the congruent condition.Additionally,there was a significant enhancement in the correlation between RDLPFC and LDLPFC(t=2.44,P=0.025).However,the differences in correlation between left and right SMA,as well as between SMA and DLPFC,were not statistically significant(P＞0.05).Conclusion These findings suggest that during speech under incongru-ent conditions,increased cognitive load leads to elevated cortical activation in the DLPFC and SMA,along with in-creased functional connectivity between the left and right DLPFC.

Objective To investigate the effect of single osteochondral defect of the knee on pressure distributions in weight-bearing area of the medial femoral condyle,and further evaluate changes of the location of peak pressure on the medial condyle with the defect size changing.Methods Ten fresh porcine knee joints were fixed in extension position.First,mechanical loads were applied to the medial compartment of the normal porcine knee joint to determine the maximum contact pressure area.Then,rounded osteochondral defects with different diameters(in depth of 9 mm)were drilled at this area,respectively.The 100,200,300 N axial compression loads were applied to the medial compartment of each knee joint,and the strength and location of the peak contact pressure during loading were recorded.Results The peak pressure increased with defect size increasing,and the phenomenon of stress concentration appeared.The peak pressure was significantly higher in the defect with diameter exceeding 8 mm than that in the non-defect knee.The peak pressure showed a similar tendency to move closer to the defect rim as the defect size increased(the distance between the peak pressure position and the defect rim,namely peak-to-rim distance,decreased).Conclusions In the single knee osteochondral defect model,when the diameter of the defect at the weight-bearing area was larger than 8 mm,the peak pressure on the uninjured site significantly increased,and the peak-to-rim distance significantly decreased,which implied 8 mm as a potential threshold for surgical intervention.

Objective To investigate the differences in cortical activation and functional connectivity during speech under different cognitive loads in young individuals.Methods Twenty-one participants(mean age 21.9±1.33 years)were instructed to read short sentences embedded with color words under both congruent(where the color words matched the font color)and incongruent(where the color words did not match the font color)condi-tions.The color words required reading the font color instead of the word itself.Functional near-infrared spectros-copy(fNIRS)was utilized to analyze differences in cortical activation(changes in HbO concentration)and functional connectivity(Pearson correlation of HbO between brain regions)in the dorsolateral prefrontal cortex(DLPFC)and supplementary motor area(SMA)bilaterally.Results The fNIRS results revealed significant increase in HbO con-centration changes in the RDLPFC(t=3.4,P=0.003),LDLPFC(t=2.58,P=0.019),RSMA(t=3.59,P=0.002),and LSMA(t=4.06,P=0.001)under the incongruent condition compared to the congruent condition.Additionally,there was a significant enhancement in the correlation between RDLPFC and LDLPFC(t=2.44,P=0.025).However,the differences in correlation between left and right SMA,as well as between SMA and DLPFC,were not statistically significant(P＞0.05).Conclusion These findings suggest that during speech under incongru-ent conditions,increased cognitive load leads to elevated cortical activation in the DLPFC and SMA,along with in-creased functional connectivity between the left and right DLPFC.

Objective To forecast the national nursing human resources situation and provide policy basis for promoting the development of the nurse team.Methods The registered nurse numbers,the total population,the registered(assistant)physician numbers,and the bed numbers in medical and health institutions(in thousands)were selected from 2013 to 2023,and the bed-to-nurse ratio,doctor-to-nurse ratio,and the number of nurses per thousand population were calculated and analyzed to study the changes in national nursing human resources over the past decade.A grey GM(1,1)model was established to predict the number of nurses per thousand population from 2024 to 2030.Results ① The number of nurses per thousand population has increased year by year in the past decade,with an average annual growth rate of 11.38％;② The precision of the grey GM(1,1)model for the number of nurses per thousand population is precise(α=-0.065 9,b=2.014 1,C value=0.003 3,P=1.000),with high fitting degree.And the predicted number of registered nurses per thousand population from 2024 to 2030 are 4.291,4.584,4.896,5.229,5.585,5.965,and 6.371 respectively.Conclusion The national nursing human resources allocation has been optimized in the past decade,and the GM(1,1)model predicts that the national nursing human resources change is also in an upward trend.However,relevant policies still need to be formulated to improve the bed-to-nurse ratio and doctor-to-nurse ratio.

Aim To construct a diabetic atherosclerosis mouse model and study the pathological characteristics of diabetic atherosclerosis.Methods Fifty 8-week-old male LDLR-/-mice were fed with standard diet for 2 weeks and then changed to high-fat diet,they were randomly divided into two groups.The diabetic atherosclerosis group was given intraperitoneal injection of low dose streptozotocin(STZ)for 5 days continuouly to establish the model,and the atheroscle-rosis group was given citrate buffer injection at the same time.The body mass,blood glucose and blood lipids of the mice in the two groups were detected for many times.At the age of 23 weeks,the mice were euthanized after glucose tolerance test.HE staining and oil red O staining were used to detect the gross and aortic root atherosclerosis,immunohistochemical staining was used to detect CD4,α-smooth muscle actin(α-SMA),EGF-like module-containing mucin-like hormone re-ceptor-like 1(EMR1),monocyte chemotactic protein-1(MCP-1),NOD-like receptor protein 3(NLRP3),vascular cell adhesion molecule-1(VCAM-1),matrix metalloproteinase-2(MMP-2)and tissue inhibitor of metalloproteinase-1(TIMP-1),Western blot was used to detect α-SMA,CD4,tumor necrosis factor-α(TNF-α),NLPR3,intercellular adhesion molecule-1(ICAM-1),and type Ⅰ and Ⅲ collagen.Results Compared with the atherosclerosis group,the body mass decreased,the levels of total cholesterol(TC),triglyceride(TG),low density lipoprotein cholesterol(LDLC)increased,and the levels of high density lipoprotein cholesterol(HDLC)decreased(P＜0.05)in the diabetic atherosclerosis group.Compared with the atherosclerosis group,the distribution of atherosclerotic plaques was diffuse and the area was increased in the diabetic atherosclerosis group,and the contents of lipids,T cells,macrophages,smooth muscle cells,type Ⅰ and Ⅲ colla-gen were increased(P＜0.05);the protein levels of TNF-α,MCP-1,MMP-2,NLRP3,ICAM-1 and VCAM-1 in vascular tissues were increased,while the content of TIMP-1 were decreased and MMP2/TIMP-1 were increased(P＜0.05).Conclusions LDLR-mouse model of diabetic atherosclerosis can be successfully established by STZ induction combined with high-fat diet,which can reflect the plaque composition and inflammatory characteristics of diabetes promoting atheroscle-rosis.It can be used as a relatively ideal pathological model for the study of diabetic macroangiopathy.

Objective:To explore the effect of physical activity trajectories on cognitive function in middle-aged and older adults.Methods:Based on data from the China Health and Retirement Longitudinal Study (CHARLS) from 2011 to 2020, 809 participants aged ≥45 were selected. General data, physical activity levels, and cognitive function were collected. The group-based trajectory model (GBTM) was used to establish the physical activity trajectory model, and multiple linear regression was applied to investigate factors affecting cognitive function in middle-aged and older adults and to analyze the relationship between physical activity trajectories and cognitive function.Results:The cognitive function score for the 809 middle-aged and older adults was (11.71±4.60), and the logarithmic metabolic equivalent of physical activity was (8.38±1.06). Based on GBTM, four physical activity trajectories were identified: stable group, slow-increase group, rapid-decrease group, and stable-decrease group. Multiple linear regression analysis showed that the stable and slow-increase activity trajectories, gender, age, marital status, and retirement status were significant factors influencing cognitive function in middle-aged and older adults ( P<0.01) . Conclusions:Physical activity trajectories are associated with cognitive function in middle-aged and older adults. Maintaining stable or slowly increasing physical activity is beneficial for cognitive health. Nurses should design targeted interventions based on factors influencing cognitive function.

Objective To investigate the impact of triglyceride glucose index(TyG index)during early pregnancy on glucose and lipid metabolism in gestational diabetes mellitus.Methods A total of 527 pregnant women with gestational diabetes mellitus who deliv-ered at the Huizhou First Maternal and Child Health Care Hospital from May 2021 to August 2022 were selected.Based on the early preg-nancy TyG index,they were categorized into Tigroup(＜8.273,n=176),T2group(8.273-8.590,n=175),T3group(≥8.590,n=176).The glucose and lipid metabolism at different stages of pregnancy and maternal-fetal outcomes among the three groups were compared,and to explore the influence of the TyG index on on glucose and lipid metabolism.Results As the TyG index increased in the three groups,gestational times,delivery times,newborn weight,rates of macrosomia,and cesarean section all increased significantly(P＜0.05).In the third pregnancy and postpartum,total cholesterol,high-density lipoprotein cholesterol and triglycerides increased,while low-density lipoprotein cholesterol decreased,showing statistical significance(P＜0.05).Further analysis during the postpartum period revealed no statistical differences in impaired fasting glucose and impaired glucose tolerance among the groups(P＞0.05).Howev-er,the incidence of abnormal lipid metabolism such as hypercholesterolemia,hypertriglyceridemia,and decreased high-density lipopro-tein cholesterol significantly increased,and the difference was statistically significant(P＜0.05).Conclusion A high TyG index in ear-ly pregnancy can impact lipid metabolism in the third pregnancy and the postpartum period for women with gestational diabetes mellitus,increasing the occurrence of lipid metabolism abnormalities.

Objective To forecast the national nursing human resources situation and provide policy basis for promoting the development of the nurse team.Methods The registered nurse numbers,the total population,the registered(assistant)physician numbers,and the bed numbers in medical and health institutions(in thousands)were selected from 2013 to 2023,and the bed-to-nurse ratio,doctor-to-nurse ratio,and the number of nurses per thousand population were calculated and analyzed to study the changes in national nursing human resources over the past decade.A grey GM(1,1)model was established to predict the number of nurses per thousand population from 2024 to 2030.Results ① The number of nurses per thousand population has increased year by year in the past decade,with an average annual growth rate of 11.38％;② The precision of the grey GM(1,1)model for the number of nurses per thousand population is precise(α=-0.065 9,b=2.014 1,C value=0.003 3,P=1.000),with high fitting degree.And the predicted number of registered nurses per thousand population from 2024 to 2030 are 4.291,4.584,4.896,5.229,5.585,5.965,and 6.371 respectively.Conclusion The national nursing human resources allocation has been optimized in the past decade,and the GM(1,1)model predicts that the national nursing human resources change is also in an upward trend.However,relevant policies still need to be formulated to improve the bed-to-nurse ratio and doctor-to-nurse ratio.

Objective To investigate the impact of triglyceride glucose index(TyG index)during early pregnancy on glucose and lipid metabolism in gestational diabetes mellitus.Methods A total of 527 pregnant women with gestational diabetes mellitus who deliv-ered at the Huizhou First Maternal and Child Health Care Hospital from May 2021 to August 2022 were selected.Based on the early preg-nancy TyG index,they were categorized into Tigroup(＜8.273,n=176),T2group(8.273-8.590,n=175),T3group(≥8.590,n=176).The glucose and lipid metabolism at different stages of pregnancy and maternal-fetal outcomes among the three groups were compared,and to explore the influence of the TyG index on on glucose and lipid metabolism.Results As the TyG index increased in the three groups,gestational times,delivery times,newborn weight,rates of macrosomia,and cesarean section all increased significantly(P＜0.05).In the third pregnancy and postpartum,total cholesterol,high-density lipoprotein cholesterol and triglycerides increased,while low-density lipoprotein cholesterol decreased,showing statistical significance(P＜0.05).Further analysis during the postpartum period revealed no statistical differences in impaired fasting glucose and impaired glucose tolerance among the groups(P＞0.05).Howev-er,the incidence of abnormal lipid metabolism such as hypercholesterolemia,hypertriglyceridemia,and decreased high-density lipopro-tein cholesterol significantly increased,and the difference was statistically significant(P＜0.05).Conclusion A high TyG index in ear-ly pregnancy can impact lipid metabolism in the third pregnancy and the postpartum period for women with gestational diabetes mellitus,increasing the occurrence of lipid metabolism abnormalities.