[Clinical characteristics of posterior malleolus fracture in adults].

Objective: To explore the latest clinical characteristics and development trends of posterior malleolus fracture. Methods: Clinical information of inpatients with posterior malleolus fracture in Shanghai Tongji Hospital and Karamay Central Hospital from January 2014 to December 2022 were reviewed and collected. The imaging data of patients were acquired using the Picture Archiving and Communication Systems. A statistical analysis was performed as to gender, current age, year of admission, injury mechanism, fracture type, and posterior malleolus fracture classification. Moreover, a comparative analysis was conducted on the injury mechanisms and morphological differences of posterior malleolus fracture at different periods, regions, and age groups. Results: A total of 472 patients (210 patients from Shanghai Tongji Hospital and 262 patients from Karamay Central Hospital) with posterior malleolus fracture with a mean age of (48.7±15.6) years were included in this study. The peak of posterior malleolus fracture occurs in the age group of 50-59 years. The injury mechanisms mainly involve low-energy fall and sprain (411 cases, 87.1%), followed by traffic accidents (52 cases, 11.0%), and fall injury from height (9 cases, 1.9%). The number of cases according to different fracture types showed the following descending order: trimalleolar fracture-supination extorsion (335 cases, 71.0%), bimalleolar fracture (60 cases, 12.7%), trimalleolar fracture-pronation extorsion (43 cases, 9.1%), posterior malleolus+tibial shaft fracture (19 cases, 4.0%), simple posterior malleolus fracture (15 cases, 3.2%). The numbers of cases corresponding to the Haraguchi Ⅰ, Ⅱ and Ⅲ type of posterior malleolus fractures was 369 (78.2%), 49 (10.4%), and 54 (11.4%), respectively. The Tongji ⅡA type represented the highest number of cases (249 cases, 52.8%), followed by the ⅡB type (120 cases, 25.4%), Ⅰ type (54 cases, 11.4%), ⅢB type (36 cases, 7.6%), and ⅢA type (13 cases, 2.8%). However, no obvious statistical difference was observed in the injury mechanism, Haraguchi classification, and Tongji classification of posterior malleolus fractures among different years and regions from the year of 2014 to 2022 (all P>0.05). Conclusions: The injury mechanism of posterior malleolus fracture mainly involves low-energy fall and sprain cases. The trimalleolar fracture-supination extorsion, Haraguchi Ⅰ type and Tongji ⅡA type of posterior malleolus fracture are predilection fracture types, and all present an obvious incidence peak in the age group of 50-59 years. There has been no significant change in the development trend of clinical characteristics of posterior malleolus fractures in recent years.

[Analysis of spontaneous nystagmus and the frequency characteristics of affected semicircular canals in patients with vestibular neuritis].

Objective: To investigate the spontaneous nystagmus (SN) and the frequency characteristics of affected semicircular canals in patients with vestibular neuritis (VN). Methods: This is a cross-sectional study. A total of 61 patients with VN admitted to the Department of Neurology of Shanxi Bethune Hospital from June 2020 to October 2021, 39 were male and 22 were female, with a mean age of (46±13) years old and male to female ratio of 1.77∶1. According to SN characteristics, 61 patients were divided into non-nystagmus group(nSN), horizontal nystagmus group(hSN) and horizontal-torsional nystagmus group (htSN). Clinical data were collected, and SN, unilateral weakness (UW), directional preponderance (DP), and video head impulse test (vHIT) gain were used as observation indicators. Statistical analysis by SPSS23.0 software. Normal distributed quantitative data (age, semicircular canal gain, SN intensity) were expressed by x¯±s, non-normal distributed quantitative data (disease course, UW, DP) were expressed by M(Q1,Q3), qualitative data were expressed by rate and composition ratio, difference analysis by one-way ANOVA, rank sum test, Chi-square test or Fisher's exact probability method, considered by P value<0.05. Results: (1)The disease course of nSN, hSN and htSN was 7.0 (4.0, 12.5), 6.0 (3.5, 11.5), and 3.0 (2.0, 6.5) days respectively, and there were statistical differences (χ2=7.31,P=0.026).(2)The horizontal nystagmus intensity of htSN was (16.8±8.6)°/s, which was significantly higher than that of (9.8±4.7)°/s in hSN (t=3.71, P<0.001). There was no significant difference in the positive rate of UW between the three groups (P=0.690), and there was a significant difference in the positive rate of DP in the three groups (χ2=12.23, P=0.002). The horizontal nystagmor intensity in the htSN was positively correlated with the vertical nystagmus intensity (r=0.59, P=0.001).(3)The gain of the affected horizontal canal of the three groups was statistically different (F=8.28, P=0.001), and the gain of the horizontal canal of hSN and htSN was significantly lower than that of nSN (t=2.74, P=0.008; t=4.05, P<0.001); The gain of the affected anterior canal in the three groups was statistically different (F=5.32, P=0.008). The gain of the anterior canal in both nSN and hSN was significantly higher than that in htSN (t=3.09, P=0.003; t=2.15, P=0.036). The horizontal canal gain of htSN is positively correlated with the anterior canal gain (r=0.74, P<0.001).(4)The affected semicircular canals in the two groups with no-vertical-component nystagmus (nSN and hSN) and the htSN were counted. The composition ratio of the affected semicircular canals in the two groups was different (χ2=8.34, P=0.015). Conclusion: The occurrence of SN in patients with VN is related to many factors, such as the disease course, low and high frequencies, and the severity of the condition in the affected semicircular canal.

[Distribution and reference intervals of daytime intraocular pressure in the eye health screening population of Handan].

Objective: To describe the distribution and establish reference intervals (RI) of daytime intraocular pressure (IOP) in the eye health screening population of Handan. Methods: This cross-sectional study included subjects who participated in eye health screening at the Physical Examination Center of Handan First Hospital from May 2021 to June 2022. A complete general and ocular examination was performed, including measurements of visual acuity and IOP (using Goldmann tonometry), slit lamp microscopy, fundus photography, and anterior and posterior segment optical coherence tomography. Subjects with factors that could cause significant changes in IOP or affect the accuracy of IOP measurement, or with an inability to measure IOP were excluded. Simple random sampling was used to select participants, who were grouped by gender and age (18 to <30, 30 to <40, 40 to <50, 50 to <60, 60 to <70, and ≥70 years). Central corneal thickness and IOP at 8 to 11 o'clock in one eye of each participant were recorded. The independent sample t test and ANOVA were used for statistical analysis, and the RI of IOP values was calculated by x¯±1.96s. Results: A total of 9 310 subjects had their IOP measured, and 3 491 participants (3 491 eyes) were randomly selected from 7 886 healthy subjects. The age of the participants was (47.74±14.47) years old, ranging from 18 to 90 years old. There were 1 694 males and 1 797 females. The central corneal thickness of all participants was (525.56±49.39) µm. The daytime IOP of all participants was (15.40±2.54) mmHg (1 mmHg=0.133 kPa), and the RI was 10.42 to 20.39 mmHg. The IOP was (15.49±2.58) mmHg for males and (15.29±2.49) mmHg for females, and the gender difference was statistically significant (P<0.05). The RI of daytime IOP values was 10.43 to 20.54 mmHg for males and 10.41 to 20.18 mmHg for females. There were significant differences in daytime IOP [(15.13±2.58), (15.33±2.53), (15.49±2.50), (15.53±2.55), (15.39±2.62), and (15.28±2.52) mmHg] among 6 age groups (P<0.05). Conclusions: The distribution of daytime IOP in different gender and age groups in the eye health screening population of Handan and the RIs derived from the distribution were roughly the same as the international normal IOP RI (10 to 21 mmHg). It is recommended to refer to the RI of daytime IOP values of different genders and ages for clinical decision.

Parameterized Analysis of Craniocerebral Injury Caused by Fist.

ABSTRACT: Objective Based on the theory of biomechanics, the finite element method was used to study the injury characteristics of different parts of brain hit by fist with different force and to predict the risk of craniocerebral injury, in order to provide reference for actual medical protection and forensic identification. Methods The finite element model of fist was constructed by using DICOM data modeling method and related software, and the effective mass and speed of fist were used to represent the kinetic energy of fist, and combined with human finite element model THUMS 4.02, the characteristics of craniocerebral injury caused by frontal and lateral blows were parametrically simulated. Results The probability of direct death from a blow to the head was low, but as fist power increased, so did the risk of craniocerebral injury. The characteristics of craniocerebral injury were also significantly different with the different fist hitting head locations. When the frontal area was attacked, the maximum equivalent stress of skull was 122.40 MPa, while that of brain tissue was 4.31 kPa. When the temporal area was attacked, the maximum equivalent stress of skull was 71.53 MPa, while that of brain tissue was 7.09 kPa. Conclusion The characteristics and risks of skull fracture and brain tissue injury are different when different parts of the brain are hit by fist. When the frontal area is hit, the risk of skull fracture is significantly higher than when the temporal area is hit. The risk of brain tissue injury is the opposite. The position with the highest probability of skull fracture is generally the place where the skull is directly impacted, and with the conduction of stress waves, it will spread to other parts of the skull, while the position with the highest risk of brain tissue injury is not the place where the brain is directly impacted.

[The effects and mechanism of baicalin in a mouse acute hypertensive glaucoma model].

Objective: To explore the potential neuroprotection effects and associated mechanism of baicalin in a rodent acute hypertensive glaucoma model and oxygen-glucose deprivation/reperfusion (OGD/R) induced retinal ganglion cell (RGC) injury. Methods: Experiment research. A rapid and substantial elevation of intraocular pressure was performed to establish an acute hypertensive glaucoma model, and retinal thickness was assessed at 1, 3, 5, and 7 days. The mice were then randomly divided into three groups: normal control group, hypertension group, and baicalin (50 mg/kg) for hypertension group. The effects of baicalin on the RGCs were evaluated by retrograde transporting of Fluoro-Gold. The mRNA levels of tumor necrosis factor-α, interleukine-1ß (IL-1ß), and inducible nitric oxide synthase were detected by real-time PCR, and the protein levels were measured by Western blot in the retina tissue of acute hypertensive glaucoma model. Purified primary RGC survival under OGD/R stress was measured by flow cytometry, which was also performed to measure the survival rate of RGCs pretreated by different doses of baicalin (2.5 µmol/L, 5.0 µmol/L, and 10.0 µmol/L). The effects of baicalin on primary RGCs co-cultured with mouse microglia cell line BV2 were evaluated by flow cytometry. The cytokine IL-1ß in the culture supernatant was measured by immunochemical analyses. Statistical analysis was performed using analysis of variance. Results: Retinal tissue injuries and RGC loss were observed both in vivo and in vitro. Retinal thickness was decreased to 87.32%±0.94% at 3 days (t=6.73, P<0.01), 74.86%±2.43% at 5 days (t=13.40, P<0.01), and 63.53%±2.15% at 7 days (t=19.46, P<0.01). Treatment of 50 mg/kg baicalin significantly promoted the RGC survival from 61.32%±5.94% to 89.93%±10.08% (t=4.84, P<0.01). Baicalin alleviated the retinal damages by suppressing the expression of inflammatory cytokines as revealed by Western blot and real-time PCR. In vitro the RGC survival under OGD/R stress was increased from 51.53%±1.36% to 69.37%±7.09% and 66.23%±4.25% with 5.0, 10.0 µmol/L baicalin administration (t=5.50, 4.53; both P<0.01). BV2 under OGD/R stress did extra damage to RGCs, and baicalin could reverse the damages and increase the survival from 69.37%±7.09% to 73.00%±5.20% (t=2.82, P=0.048) by reducing the release of IL-1ß [(39.97±8.76) pg/ml vs. (61.33±5.78) pg/ml, t=4.19, P=0.010]. Conclusion: Baicalin could alleviate retina tissue injury directly and promote the survival of RGCs by downregulating the expression of inflammatory cytokines and protecting RGCs from ischemia reperfusion injury. (Chin J Ophthalmol, 2020, 56: 376-382).

[Analysis of Influencing Factors of Single Camera Photogrammetry in Forensic Three-Dimensional Reconstruction].

ABSTRACT: Objective To evaluate the influence of factors such as the selection of equipment, focal length and the selection of reconstruction quality in the reconstruction software on the reconstruction results of single camera photogrammetry and provide reference for the forensic application of single camera photogrammetry. Methods The 19 skulls were measured by traditional measurement method and single camera photogrammetry. The differences between the two measurement methods and within the group with same equipment but different focal length were analyzed. One skull and one corpse were selected as the research objects. According to the reconstruction quality selection conditions in the photogrammetric software, the experimental group was divided into five grades. The model reconstructed by optical scanner was defined as reference model, while the model reconstructed by single camera photogrammetry was defined as test model. The test model was aligned with the reference model, 3D deviation analysis was carried out and the mean error and root mean square （RMS） values were calculated. Results The differences between EOS 7D zoom group and traditional measurement, and within the group with same equipment had statistical significance （P<0.05）. The mean error value and minimum RMS value of the skull reconstructed by single camera photogrammetry and the three-dimensional model of the corpse existed in the medium quality group, and the trend was basically the same. Conclusion The equipment and focal length has no obvious influence on the results of single camera photogrammetry. Lower reconstruction quality can easily cause distortion, while higher reconstruction quality can easily generate noise, so medium quality is preferred.

Exploring of the Mechanism of Rib Fracture Caused by Landing on Different Parts of the Trunk after Falls from Height Using Finite Element Method.

ABSTRACT: Objective To study the mechanism of rib fracture caused by landing on different parts of the trunk using finite element method, and to provide some new techniques and new ideas for the reconstruction of the whole process of falls from height. Methods The finite element method was used to study the rib fracture of human security model THUMS4.0 caused by landing on different parts of the trunk. Then the model was compared with actual cases and the mechanism of rib fracture caused by falls from height was analyzed from a biomechanical point of view. Results There were some differences in the stress and strain distribution as well as the rib fracture sites when different parts touched the ground. Ribs on both sides of the body were fractured when the front of the trunk touched the ground, and the fractures were mainly located in the junction of the ribs and costal cartilage and the midaxillary line area. When the right anterior part of the trunk touched the ground, rib fracture occurred first on the side that touched the ground, and rib fractures were mainly located in the area from the right midaxillary line to the posterior axillary line, and junction of ribs on both sides and costal cartilage. When the back of the trunk touched the ground, the fracture sites were mainly located on the back of the ribs on both sides. When the right posterior part of the trunk touched the ground, multiple rib fractures were likely to occur in the parts that touched the ground. The plastic strains were mainly concentrated at the fracture sites, while the von Mises stresses were not only concentrated at the fracture sites, but also at other sites. Conclusion There are some differences in rib fracture location sites and injury mechanisms when different parts of the trunk touch the ground.

Evaluation of 3D Measuring Methods for Body Surface Damage and Scars.

ABSTRACT: Objective To assess the accuracy and reliability of the two 3D measuring methods, structured-light scanning and single-camera photogrammetry in forensic body surface damage and scar measurement. Methods The measuring results of 86 injuries by the ruler method, structured-light scanning and single-camera photogrammetry were compared and evaluated. The area measuring results of 13 simulated scars by the structured-light scanning, single-camera photogrammetry, Photoshop lasso pixel method and PDF reading software were compared and evaluated. The time consumed was recorded. The known specification information of the stickers was used as the standard value to compare the measuring accuracy of the ruler method, structural-light scanning and single-camera photogrammetry, and to calculate the root mean square error （RMSE）. The consistency evaluation of intraclass correlation coefficient （ICC） for the repeatability of 3 measuring results obtained by different operators and the same operator. Results The differences in results of the two 3D measuring methods and the ruler method had no statistical significance; the differences between measuring results made by the structured-light scanning, single-camera photogrammetry and PDF reading software and that of the Photoshop lasso pixel method had no statistical significance. The post-processing of the single-camera photogrammetry consumed more time than that of other methods. When the long-distance group （10-40 cm） was measured, the results obtained by the ruler method were shorter than the standard value. The RMSE value results were structured-light scanning < single-camera photogrammetry < ruler method. The ICC value intragroup and intergroup were greater than 0.99. Conclusion Both structured-light scanning and single-camera photogrammetry can be applied in recording and measuring forensic body surface damage. The former has better performance in measurement accuracy and stability, while the latter has better color performance but longer post-processing time.

[Research Status of Postmortem MSCT Angiography in Forensic Science].

ABSTRACT: Virtual autopsy is a new technique for investigating the morphological changes of cadaveric tissues and organs by medical imaging technology. It has been widely used in the identification of causes of death. Multislice spiral computed tomography （MSCT） has become a routine inspection method in some identification institutions, although it cannot completely replace traditional autopsy, it plays a key auxiliary or substitute role in the identification of certain abnormal causes of death. Plain MSCT scan cannot visualize cadaveric vessels, but can perform cadaveric angiography to determine vascular injury or disease. This technology has entered a rapid development period in recent years, and has made a considerable progress in contrast agent, perfusion methods and imaging methods. This article summarizes several common cadaveric MSCT angiography methods, such as systemic angiography, angiography through cardiopulmonary resuscitation, targeted angiography, and angiography by cardiac puncture, and analyzes and compares the application prospects.

[Selective tarsometatarsal arthrodesis for old Lisfranc injury].

Objective: To discuss the methods and clinical outcomes of selective tarsometatarsal (TMT) arthrodesis for old Lisfranc injury. Methods: The clinical data of 36 cases with old Lisfranc injury treated by selective arthrodesis from January 2010 to October 2016 in the Department of Orthopedics in Shanghai Sixth People's Hospital were analyzed retrospectively. There were 16 males and 20 females in this group with a mean age of (40±6) years. The information of pre-operative and post-operative X-ray, American Orthopaedics Foot and Ankle Society (AOFAS) midfoot score and pain Visual Analogue Scale (VAS) score was collected. The complications were also recorded. The pre- and post-operative data were compared with t test. Results: The 36 patients got a follow-up for at-least 2 years (averaged (4.3±1.6) years, ranged from 2 to 8 years). The post-operative AOFAS midfoot score was improved from (44±7)(28-60) to (83±7)(76-97)(t=-37.1, P<0.05), and the VAS score decreased from (6.3±2.5)(5-9) to (1.6±1.3)(0-3)(t=23.7, P<0.05). Implant breakage occurred in two patients and the symptom was relieved after the removal of implants. Conclusion: The selective TMT arthrodesis for old Lisfranc injury may relieve the symptoms, improve the function and life quality of patients by restoring the medial arch and midfoot and forefoot alignment.

[Organizing an assembly to eliminate hepatitis B virus through a project zero mother-to-child transmission of hepatitis B virus].

The China Foundation of Hepatitis Prevention and Control (CFHPC) initiated a project named, "getting to zero mother-to-child transmission of Hepatitis B," in July 2015, which aims to further reduce the incidence of mother-to-child transmission through standardized follow-up management of pregnant women and their infants with chronic hepatitis B virus infection by means of mobile medical application. Over the past three years, the project has established a nationwide collaborative network for interruption of mother-to-child transmission of hepatitis B virus, with 123 hospitals as project members. In addition, it has formulated a technical guidance document (Clinical Management Algorithm for Interrupting Mother-to-Child Transmission of HBV), which is designed and developed as a mobile medical application (SHIELD APP), and was released in an international conference on the theme to eliminate viral hepatitis. Following the measures mentioned above, the public's awareness rate of hepatitis B have been raised, and a good social atmosphere has been formed, which has played a positive role in promoting the prevention and control of viral hepatitis in China.

Research Progress on Postmortem Changes of Computed Tomography Imaging Characteristics on Corpses.

ABSTRACT: Postmortem changes on corpses appear immediately after death, and can transform the original structure characteristics of the corpse to different degrees as well as show specific changes on computed tomography （CT） images, sometimes with false positives and false negatives, influencing the identification of injuries or diseases. This paper systematically summarizes the postmortem changes of computed tomography imaging characteristics on corpses, to further expand the application of virtopsy in the practices of forensic pathology identification, and provide reference for the identification of injuries, diseases and changes after normal death.

[Dynamic investigation of nutritional risk in patients with malignant tumor during hospitalization].

Objective: To prospectively investigate the changes in nutritional status of patients with malignant tumors during hospitalization by using nutritional risk screening (NRS2002), and to analyze the correlation between the nutritional status and clinical outcomes . Methods: This was a prospective and parallel research done by multi-center collaboration from 34 hospitals in China from June to September 2014.Hospitalized patients with malignant tumors inthese departments (Department of Gastroenterology, respiratory medicine, oncology, general surgery, thoracic surgery and geriatrics)were investigated. Only the patients with age≥ 18 years and hospitalization time between 7-30 days were included. During hospitalization, the physical indexes of human bodywere measured, and the NRS 2002 scores, and monitored the nutritional support at the time points of admission and 24 hours before discharge were recorded.And whether there was a nutritional risk in hospitalized patients and its association with clinical outcomes were investigated. Results: A total of 2 402 patients with malignancies were enrolled in this study. Seventy fourpatients who did not complete NRS2002 were eliminated, and 2 328 patients were included. The number of the main diseases was the top five, including 587 cases of colorectal cancer, 567 cases of lung cancer, 564 cases of gastric cancer, 146 cases of esophageal cancer, and 119 cases of liver tumor. At the time of discharge, compared with admission, the BMI, body weight, grip and calf circumferences of patients with malignant tumor were significantly decreased (P<0.05). The total protein, albumin, prealbumin and hemoglobin were significantly lower than those at admission (P<0.05). In 2 328 patients who were completed nutritional risk screening, the rate of malnutrition at admission was 11.1% (BMI =18.5, 258/2 328) and the rate of malnutrition at discharge was 10.9% (BMI =18.5, 254/2 328), there were no significant differences (χ(2)=0.019 7, P=0.888). There were 1 204 patients with nutritional risk at admission (51.7%, NRS2002 score≥3)and 1 352 patients with nutritional risk at discharge (58.1%, NRS2002 score≥3), with significant differences (χ(2)=49.9, P<0.001). The incidence of nutritional risk in patients with colorectal, stomach, and lung tumors at discharge was significantly higher than that at admission (P<0.05). The infective complications and other complications of patients with nutritional risk were significantly greater than those without nutritional risk at admission and at discharge.ICU hospitalization stay of patients with nutritional risk was increased significantly than those without nutritional risk at admission(P=0.042). Hospitalization expenses of patients with nutritional risk was increased significantly than those of patients without nutritional risk at discharge(P<0.01). Conclusion: The patients with malignant tumor have a higher incidence rate of malnutrition at both admission and discharge and malnutritionhas correlation with adverse clinical outcomes.The aboveindicators did not improve significantly at discharge.Doctors should pay more attention to the nutritional status (screening and evaluation)of patients before discharge and use appropriate and adequate nutrition support in order to prevent the weight loss and improve the life quality of patients.

[Study on the metastatic sequence of cervix lymph node in hypopharyngeal carcinoma].

Objective: To investigate the metastatic sequence of cervical lymph node in hypopharyngeal carcinoma aimed at guiding neck exploration. Methods: Seventy-five serial sections of integrally dissected lateral neck specimens from 67 patients of hypophayryngeal carcinoma were histopathologically observed, and the metastatic sequence of cervical lymph node of hypophayryngeal carcinoma were analysed. Results: In 75 integrally dissected lateral neck specimens, 63 laterals were found to occur cervical lymph node metastases, the metastatic ratio was 84.0%. The analytic result of 63 dissected lateral neck specimens with positive lymph nodes showed that the metastatic lymph node ratio in descending order was level Ⅱ (90.5%), level Ⅲ (76.2%), level Ⅳ (41.3%), level Ⅴ (15.9%), level Ⅰ (7.9%) and level Ⅵ (3.2%). The metastatic ratio of lymph node between level Ⅰ~Ⅵ were significantly different from each other (P<0.01). When the tumor metastasized to one cervical lymph node, this could be found in levels Ⅱ or Ⅲ, when metastasized to two cervical lymph nodes, these could be found in levels Ⅱ, Ⅲ, Ⅳ, and when metastasized to more than 5 of cervical lymph nodes, these could be found in levels Ⅱ, Ⅲ, Ⅳ, Ⅴ, Ⅰand Ⅵ. According to the occurring sequence, metastatic ratio and number of cervical lymph node metastasis (LNM), levels Ⅱ and Ⅲ were identified as the first station, level Ⅳ was the second station and levels Ⅴ, Ⅰ and Ⅵ were the third station of cervical LNM in hypopharyngeal carcinoma. Conclusion: The confirmation of metastatic sequence of cervical lymph node in hypophayryngeal carcinoma provides a reliable evidence for neck lymph node dissection and reference value for clinic therapy.

[Diagnostic Value of Postmortem CT Angiography in Coronary Atherosclerosis].

OBJECTIVES: To explore the application value of postmortem computed tomography （CT） angiography on diagnosis of coronary atherosclerotic stenosis degree. METHODS: Based on the previous experimental results, the postmortem CT angiography device of human isolated heart was improved. Different coronary atherosclerotic stenosis degree of sudden death cases was selected. Before the cardiac anatomy, hearts were removed out completely and CT angiography was performed immediately. The CT angiography results were compared with histopathological findings. Meanwhile, the advantages and disadvantages of the angiography device before and after improvement were compared. RESULTS: The improved angiography device of isolated heart could get better imaging results. The postmortem CT angiography results had high consistency with the histopathological findings on diagnosis of coronary atherosclerotic stenosis degree. And the coronary artery lesions could be revealed more objectively and vividly by 3D reconstruction technology. However, CT angiography could only be used to examine the pathological changes of blood vessels, which might have some limitations on the diagnosis of cause of death. CONCLUSIONS: Postmortem CT angiography can be used as an additional method for the conventional autopsy in the cases of coronary atherosclerosis.

[Research Progress of MALDI-TOF-IMS in Biomedicine and Its Application Prospect in Forensic Sciences].

Matrix-assisted laser desorption/ionization time-of-flight imaging mass spectrometry （MALDI-TOF-IMS） can analysis unknown compounds in sections and obtain molecule imaging by scanning biological tissue sections, which has become a powerful tool for the research of biomarker, lipid distribution and drug metabolism, etc. This article reviews the application of this technique in protein identification, clinical application, drug discovery, lipid research and brain injury.

[Reconstruction of Vehicle-human Crash Accident and Injury Analysis Based on 3D Laser Scanning, Multi-rigid-body Reconstruction and Optimized Genetic Algorithm].

OBJECTIVES: To reconstruct a vehicle-bicycle-cyclist crash accident and analyse the injuries using 3D laser scanning technology, multi-rigid-body dynamics and optimized genetic algorithm, and to provide biomechanical basis for the forensic identification of death cause. METHODS: The vehicle was measured by 3D laser scanning technology. The multi-rigid-body models of cyclist, bicycle and vehicle were developed based on the measurements. The value range of optimal variables was set. A multi-objective genetic algorithm and the nondominated sorting genetic algorithm were used to find the optimal solutions, which were compared to the record of the surveillance video around the accident scene. RESULTS: The reconstruction result of laser scanning on vehicle was satisfactory. In the optimal solutions found by optimization method of genetic algorithm, the dynamical behaviours of dummy, bicycle and vehicle corresponded to that recorded by the surveillance video. The injury parameters of dummy were consistent with the situation and position of the real injuries on the cyclist in accident. CONCLUSIONS: The motion status before accident, damage process by crash and mechanical analysis on the injury of the victim can be reconstructed using 3D laser scanning technology, multi-rigid-body dynamics and optimized genetic algorithm, which have application value in the identification of injury manner and analysis of death cause in traffic accidents.

Experimental Ten-Photon Entanglement.

We report the first experimental demonstration of quantum entanglement among ten spatially separated single photons. A near-optimal entangled photon-pair source was developed with simultaneously a source brightness of ∼12 MHz/W, a collection efficiency of ∼70%, and an indistinguishability of ∼91% between independent photons, which was used for a step-by-step engineering of multiphoton entanglement. Under a pump power of 0.57 W, the ten-photon count rate was increased by about 2 orders of magnitude compared to previous experiments, while maintaining a state fidelity sufficiently high for proving the genuine ten-particle entanglement. Our work created a state-of-the-art platform for multiphoton experiments, and enabled technologies for challenging optical quantum information tasks, such as the realization of Shor's error correction code and high-efficiency scattershot boson sampling.

[Finite element analysis of astigmatic keratotomy based on corneal biomechanical properties].

OBJECTIVE: To establish a finite-element biomechanical model of astigmatic keratotomy, and to investigate the impact of surgical parameters on corneal deformation, stress distribution and astigmatism correction. METHODS: With Rhinoceros modeling and Abaqus finite element analysis software, a three-dimensional finite-element model of astigmatic cornea was developed, and surgical parameters such as incision optical zone, incision depth and length were varied. Postoperative corneal stress, apical deformation and astigmatism correction were assessed. RESULTS: A significant increase of stress was noticed near corneal incisions, and maximum corneal stress decreased with the increase of incision depth. Both anterior and posterior corneal surface moved slightly forward postoperatively. Maximum corneal stress was 340 392, 361 022 and 214 187 Pa, and anterior and posterior apical deformation was 49.80, 51.64, 55.53 µm and 54.15, 55.91, 59.67 µm, with 45°, 60° and 90° in arc length of the incision, respectively. The refractive power decreased in steep meridian and increased in flat meridian, resulting in a total decrease of corneal astigmatism. The magnitude of astigmatism correction was 0.85, 1.59, 2.23 and 3.06 D with 30°, 45°, 60° and 90° in arc length of the incision, respectively. CONCLUSIONS: The finite-element biomechanical model of astigmatic keratotomy could be used to predict the optical outcomes after surgery. The magnitude of astigmatism correction is positively correlated with the surgical incision arc length. (Chin J Ophthalmol, 2016, 52: 674-680).