In animal navigation, head direction is encoded by head direction cells within the olfactory-hippocampal structures of the brain. Even in darkness or unfamiliar environments, animals can estimate their head direction by integrating self-motion cues, though this process accumulates errors over time and undermines navigational accuracy. Traditional strategies rely on visual input to correct head direction, but visual scenes combined with self-motion information offer only partially accurate estimates. This study proposed an innovative calibration mechanism that dynamically adjusts the association between visual scenes and head direction based on the historical firing rates of head direction cells, without relying on specific landmarks. It also introduced a method to fine-tune error correction by modulating the strength of self-motion input to control the movement speed of the head direction cell activity bump. Experimental results showed that this approach effectively reduced the accumulation of self-motion-related errors and significantly enhanced the accuracy and robustness of the navigation system. These findings offer a new perspective for biologically inspired robotic navigation systems and underscore the potential of neural mechanisms in enabling efficient and reliable autonomous navigation.
Animals ; Neural Networks, Computer ; Calibration ; Spatial Navigation/physiology* ; Head Movements/physiology* ; Neurons/physiology* ; Models, Neurological ; Head/physiology* ; Action Potentials/physiology*

AIM: To investigate the preoperative ocular symptoms and the characteristics of asymptomatic ocular surface abnormalities in hospitalized patients with primary pterygium.METHODS: Cross-sectional study. Hospitalized patients diagnosed with primary pterygium and scheduled to receive pterygium excision surgery at the Xiamen Eye Center of Xiamen University from August 2022 to October 2022 were enrolled. Ocular surface disease index questionnaire(OSDI), six examinations including non-invasive tear film break-up time, Schirmer I test, tear meniscus height, lid margin abnormality, meibomian gland dropout and tear film lipid layer thickness, and anterior segment optical coherence tomography(AS-OCT)were performed and statistically analyzed.RESULTS: A total of 178 cases(178 eyes), with a mean age of 54.39±10.75 years old, were recruited, including 75 males(42.1%)and 103 females(57.9%). The average values of ocular surface parameters in these patients included OSDI: 11.47±9.69, tear film break-up time: 7.10±3.86 s; tear meniscus height: 0.16±0.07 mm, Schirmer I test values: 14.39±7.29 mm/5 min, and pterygium thickness: 504.74±175.87 μm. Totally 161 eyes(90.4%)presented with abnormal lid margin, 44 eyes(24.7%)presented with meibomian gland dropout score ≥4, 52 eyes(29.2%)presented with low lipid layer thickness. In the 6 objective examinations, abnormalities in at least 4 of these tests were found in 85.4% of eyes. Pterygium morphology was classified into four grades: 10 eyes(5.6%)of grade Ⅰ, 93 eyes(52.2%)of grade Ⅱ, 60 eyes(33.7%)of grade Ⅲ, and 15 eyes(8.4%)of grade Ⅳ. In patients with a higher grade of pterygium, the tear film break-up time was lower, and the proportion of abnormal lid margin was also significantly higher(P<0.05). The patients were further divided into two subgroups, including 121 eyes(68.0%)with normal OSDI <13 in the normal group and 57 eyes(32.0%)with OSDI ≥13 in the abnormal group. No significant difference was found in the proportion of meibomian gland dysfunction between the two groups of patients(71.9% vs. 71.9%, P=0.872). In addition, there were differences in the number of abnormal objective examinations(4.11±0.85 vs. 4.91±0.99, P<0.001).CONCLUSIONS: Asymptomatic ocular surface abnormalities were present preoperatively in patients hospitalized for primary pterygium. A comparable high incidence of structural or functional meibomian gland dysfunction existed in pterygium patients with or without apparent ocular discomfort. More attention should be paid to the ocular surface abnormalities in those asymptomatic patients before primary pterygium surgery.

Objective: To understand the distribution of tobacco retailer within 100 meters outside middle schools in Wuhan City and its impact on smoking behavior of middle school students, so as to provide basis and feasible suggestions for the development of tobacco control policy for adolescents. Methods: From February to May 2023, a multi stage stratified cluster random sampling method was used to select 20 middle schools from 4 districts in Wuhan City. To investigate the distribution of tobacco retailer within 100 metres outside the school and the sale of tobacco to minors. A total of 4 882 students were surveyed using the core questions of the 2021 Chinese Adolescent Tobacco Prevalence Questionnaire. Fisher exact probability test, Chi square test and Chi square trend test were used for statistical analysis. Results: Nearly 70.00% of middle schools had tobacco retailer within 100 metres, with an average of (1.10±0.97) per middle school. The awareness rate (100.00%) and labeling rate (87.50%) of licensed tobacco retailer were higher than those of non licensed tobacco retailer (33.33%, 16.67%) ( P <0.05). The rates of tried smoking, current smoking and buying cigarettes within 30 days were 7.13%, 1.99% and 2.54%, respectively. The rates of students who tried smoking ( 8.58 %), current smoking (2.29%) and buying cigarettes within 30 days (2.85%) in schools with tobacco retailer within 100 metres were higher than those in schools without tobacco retailer (3.79%, 1.28%, 1.83%)( χ 2=35.80, 5.37, 4.37 , P <0.05). And as the grade increased, the rates of tried smoking, current smoking and buying cigarettes among middle school students all showed an upward trend ( χ 2 trend =66.20, 36.10, 16.17, P <0.05). Conclusions Middle school students in Wuhan City have high tobacco availability. The findings suggest that school ban should be extended from 50 meters to 100 meters, and the regulatory authorities must strictly prohibit selling tobacco products to minors at tobacco retailer.

Biliary tract carcinoma exhibits high heterogeneity at the genomic,epigenetic,and molecular expression levels.The patients even with the same pathological morphology and clinical stage of biliary tract malignant tumors have substantial differences in the treatment response and prognosis.Traditional pathological histology and clinical classifications are no longer sufficient to meet the demands of the precision medicine era.Molecular subtyping has the potential to provide more personalized cancer treatment strategies.It not only helps to reveal the mechanisms of tumor development and accurately predict disease prognosis,but also plays a crucial role in guiding the development of novel targeted drugs and implementing targeted therapies for specific tumors.With the ongoing development of precision medicine,the role of molecular subtyping in cancer diagnosis,treatment option,and prognosis assessment is increasingly prominent.This paper systematically reviewed the recent progress in the molecular subtyping of biliary tract malignant tumors based on domestic and international clinical and basic research.

Objective To compare the accuracy of the original-mirror alignment algorithm and a landmark-indepen-dent method in constructing the midsagittal plane(MSP)of the cone beam computed tomography in patients with facial deformities,so as to provide a theoretical basis for symmetric analysis.Methods The study was approved by the hospi-tal ethics committee.Cone beam computed tomography data of 30 patients with facial deformities were obtained,and the output was saved in DICOM format.The scan data were imported into Mimics 21.0;after segmentation,three-dimension-al(3D)skull models were reconstructed.Furthermore,the 3D scan data of skulls were transformed into mirror skull models using Geomagic Studio 2014 reverse engineering software.The MSP of each skull was generated using both the original-mirror alignment algorithm and the landmark-independent method.Original-mirror alignment algorithm:the original skull model and its mirror model were combined,and the new data to calculate the MSP(S1)of the original data in Geomagic Studio 2014 were obtained.Landmark-independent method:the following anatomical landmarks were deter-mined using Mimics 21.0:nasion(N),crista galli(CG),sella(S),basion(Ba),vomer(V),posterior nasal spine(PNS),in-cisive foramen(IF),and anterior nasal spine(ANS).The MSP(S2)of best fit was then found by minimizing the mean square distance of these eight anatomical landmarks to a plane in Geomagic Studio 2014.The results of the S1 and S2 models constructed using the original-mirror alignment algorithm and the landmark-independent method,respectively,were scored subjectively by five senior maxillofacial surgeons,and a paired t-test was performed for the two groups.The internal consistency analysis was performed based on secondary experiments to verify the repeatability of the expert evaluation method.Results The average scores of the S1 and S2 models were 65.73 and 75.90,respectively.The aver-age score of the model constructed using the landmark-independent method was significantly higher than that of the model constructed using the original-mirror alignment algorithm(P＜0.01).Furthermore,the results of the internal con-sistency analysis showed that the expert evaluation method had good reliability and validity.Conclusion In patients with facial deformities,the MSP constructed using the landmark-independent method is superior to that constructed us-ing the original-mirror alignment algorithm.This study provides a theoretical basis for maxillofacial symmetry analysis in clinical settings and is clinically feasible.

Objective To establish an ultra-high performance liquid chromatography(UPLC)fingerprint and multi-index content determination method of Siraitiae fructus standard decoction.Methods 15 batches of Siraitiae fructus from different producing areas were collected,Siraitiae fructus standard decoction was prepared according to Technical Requirements for Quality Control and Standardization of Traditional Chinese Medicine Formula Granules,and the extract rate was calculated.UPLC was used to establish the fingerprint of 15 batches of Siraitiae fructus standard decoction and determine the contents of 11-O-mogroside V,kaempferitrin and mogroside V,which were the main effective components.The chemometrics analysis was used to evaluate the quality of Siraitiae fructus standard decoction and find possible quality markers.Results The extraction rate of 15 batches Siraitiae fructus standard decoction ranged from 24.79％to 34.95％.There were 16 common peaks in the fingerprint,and 4 components were identified.The Siraitiae fructus standard decoction was divided into 2 categories by chemometrics analysis,among which samples from Liuzhou,Guangxi were in one category and samples from Guilin,Guangxi were in another category.Seven differential markers were screened out under the condition of variable importance projection value,and the order was as follows:peak 8＞peak 7＞peak 5＞peak 12(kaempferitrin)＞peak 1＞peak 13＞peak 4.The contents of kaempferitrin,11-O-mogroside V and mogroside V in samples from Guilin,Guangxi were slightly higher than those in samples from Liuzhou,Guangxi.Conclusion The UPLC fingerprint and content determination method established in this study are feasible,which can provide a basis for the quality evaluation of Siraitiae fructus.The results of principal component analysis show that kaempferol is likely to become a quality marker of Siraitiae fructus.

Objective To establish Cdh5-Cre ERT /Acta2-tdTomato-STOP floxed -eGFP knockin genetic tracing mice, and to investigate its application in studies on vascular endothelial cell transition in liver fibrosis. Methods Cdh5-Cre ERT mice were mated with Acta2-KI mice, and the Cdh5-Cre ERT /Acta2-KI genetic tracing mice were obtained and identified by PCR genotyping. Primary liver sinusoid endothelial cells (LSECs) were isolated and cultured, and a model of CCl 4 -induced liver fibrosis was established. LSECs and liver tissue were collected for immunofluorescent staining to observe the expression of the fluorescent proteins tdTomato and eGFP. Results After being induced by tamoxifen, LSECs and liver tissue of Cdh5-Cre ERT /Acta2-KI genetic tracing mice expressed eGFP under the conditions for epithelial-mesenchymal transdifferentiation established in vivo and in vitro, while the control group without induction expressed tdTomato alone. Conclusion The successfully established Cdh5-Cre ERT /Acta2-KI genetic tracing mice can realize the effective labeling of epithelial-mesenchymal transdifferentiation, which provides a genetic tracing basis for the diverse sources of mesenchymal myofibroblasts in liver fibrosis.

Objective:To investigate the impact of recombinant human epidermal growth factor (rh-EGF) on the epithelial recovery and the tear film stability after trans-epithelial corneal collagen crosslinking in patients with progressive keratoconus.Methods:A randomized controlled clinical trail was designed.Consecutive 66 patients (37 males and 29 females) with an average age of (21.27±3.80) years old diagnosed with primary progressive keratoconus and hospitalized in Xiamen Eye Center Affiliated to Xiamen University from October, 2016 to January, 2017 were enrolled and treated with unilateral enhanced transepithelial corneal crosslinking surgery by iontophoresis, and the patients were randomly divided into control group and experimental group according to random number table method, with 33 patients 33 eyes in each group.The eyes in the control group were treated with carboxy-methylcellulose sodium lubricant eye drops and the eyes in the experimental group were treated with rh-EGF eye drops.The ocular surface disease index (OSDI) questionare, slit lamp examination, Schirmer Ⅰ test, corneal fluorescein sodium staining scoring, non-contact tonometry, uncorrected visual acuity, best corrected visual acuity, bulbar conjunctival congestion scoring, lacrimal sevretion test, non-invasive break-up time of tear film (NIBUT), as well as tear meniscus height analysis were performed before surgery, and on day 1, day 3, day 5, day 7, day 14 and day 28 after surgery.This study followed the Declaration of Helsinki.The study protocol was approved by the Ethics Committee of Xiamen Eye Center Affiliated to Xiamen University (No.2016-ME-003).Results:On day 7 after surgery, the OSDI values were increased in both groups than the preoperative value, while the value in the experimental group was significantly lower than that in the control group ( P<0.05). There were statistically significant differences in the overall corneal epithelial staining score values between the two groups at different time points ( Fgroup=16.701, P<0.01; Ftime=454.418, P<0.01). The corneal epithelial staining score in the experimental group on day 3 and day 5 after surgery were significantly lower than those in the control group (1.79±0.65 vs. 2.70±0.68; 0.91±0.46 vs. 1.55±0.51) (both at P<0.01). The conjunctival congestion score in the experimental group was significantly lower than that of the control group on day 3 and day 5 after surgery (both at P<0.05). There were statistically significant differences in the overall NIBUT values between the two groups at different time points ( Fgroup=13.084, P<0.01; Ftime=34.383, P<0.01). The NIBUT values were significantly decreased rapidly on day 7, day 14 and day 28 after surgery in both groups (all at P<0.01), but gradually recovered.The NIBUT of the experimental group on day 7 and day 14 after surgery were significantly higher than those of the control group ([8.18±2.26]seconds vs. [5.93±2.33]seconds; [9.49±1.95]seconds vs. [7.52±2.27]seconds) (both at P<0.01). No statistical differences were found in the tonometry value, visual acuity, value of Schirmer I test as well as tear meniscus height at any time point before or after surgery between the two groups (all at P>0.05). Conclusions:Recombinant human epidermal growth factor has positive effects in the patients received enhanced transepithelial corneal crosslinking surgery, presenting with promotion of epithelial healing, relief of post-operative discomfort, and the recovery of tear film stability.

OBJECTIVE: To investigate the effect of bisphenol A exposure on the expression of DNA methyltransferase(Dnmt) gene in mouse Leydig cell line TM3 cells. METHODS: TM3 cells were randomly divided into 0, 20, 50, 125 and 300 μmol/L dose group(0 μmol/L dose group was the control group). Cells were treated with various concentration of bisphenol A solution for 24 hours.The viability of TM3 cells was determined by CCK-8 method, and the mRNA expression of Dnmt1, Dnmt3 a and Dnmt3 b was detected by real-time fluorescence quantitative polymerase chain reaction. RESULTS:The viability of TM3 cells decreased with the increasing doses of bisphenol A(P<0.01). The relative mRNA expression of Dnmt1 in TM3 cells decreased with the increase of doses of bisphenol A(P<0.01).The relative mRNA expression of Dnmt3 b in TM3 cells in the 20, 50, 125, 300 μmol/L dose group was lower than that in the control group(P<0.05).There was no statistical significant difference in the relative mRNA expression of Dnmt3 a in TM3 cells in these 5 groups(P>0.05). CONCLUSION: Bisphenol exposure is cytotoxic to TM3 cells. This toxic effect may be related to changes in Dnmt mRNA expression.

Objective To analyze the risk factors of cerebral microbleeds (CMBs) in acute cerebral infarction patients. Methods We consecutively included 255 acute cerebral infarction patients who were admitted in Neurology Department of the First Affiliated Hospital of Fujian Medical University from January 2014 to December 2016. According to the number and location of CMBs, the patients were divided into infratentorial, cortical and deep cerebral groups, each of which included non-mild and moderate-severe subgroups. The differences of the level of glomerular filtration rate (eGFR) and some common arteriosclerotic risk factors were analyzed between subgroups, and the multiple logistic regression analysis was performed. Results A total of 140 subjects (54.9%) had CMBs. In the infratentorial group, the proportion of patients who were with low eGFR level in the moderate-severe CMBs subgroup was higher than in the non-mild CMBs subgroup (P=0.024). The low eGFR level (OR=3.874, 95% CI:1.261～11.901, P=0.018) and the long duration of hypertension (OR=2.128, 95%CI: 1.004～4.510, P=0.018) were the independent risk factors of the moderate-severe infratentorial CMBs. Conclusion The low eGFR level and long duration of hypertension are risk factors for the moderate and severe infratentorial CMBs after acute ischemic stroke.