Determination of lead isotope ratios by inductively coupled plasma mass spectrometry and comparison of lead isotope ratios among different samples / 环境与职业医学

background The lead isotope ratios (LIR) differ among different sourced samples. Previous domestic and oversea studies on source tracing by LIR in human blood or urine mainly focused on the comparison of blood or urine samples from the same or different individuals, while few comparisons between biological and environmental samples, and the reported relative standard deviations (RSDs) of the main LIR (207/206Pb and 208/206Pb) fluctuate widely from 0.3% to 1%. Objective To optimize inductively coupled plasma mass spectrometry (ICP-MS), obtain a better RSD, and determine LIRs of human blood, urine, and related environmental samples. Methods The ICP-MS was optimized for operating conditions and parameters according to the sensitivity and RSD of LIR. The study subjects were 40 lead-exposed workers in a lead-acid battery factory and 2 lead poisoned children in a hospital. The samples included 40 blood and 40 urine samples from the workers before shift, 4 dust samples and 2 water samples in the workplace on the same day before shift, 2 blood and 3 urine samples from the children before hospital admission due to lead-poisoning, and 4 urine samples after medical treatment. After heating and acid digestion, the LIR (207/206Pb and 208/206Pb) of biological and environmental samples were determined by the optimized ICP-MS method. t-test and two-dimensional traceability graphics were adopted to analyze the detection results. Results The calibrated RSDs of the LIR (207/206Pb and 208/206Pb) of lead isotope standard solution were 0.11% and 0.08% respectively, and the NIST-SRM-981 actual values were 0.91531±0.00097 and 2.1670±0.0017, respectively. When the total concentration of lead was greater than 5 μg·L−1, the RSD of each isotope ratio was stable gradually; when the total concentration of lead was between 10-80 μg·L−1, the RSD was below 0.20%. There were statistically significant differences in the blood and urine LIR (207/206Pb and 208/206Pb) of the lead-exposed workers (t=5.831, P<0.001; t=21.021, P<0.001), the LIR (207/206Pb and 208/206Pb) between workplace dust samples and workers’ urine samples (t=−6.879, P=0.038; t=12.521, P<0.001), and the 208/206Pb between workplace dust samples and workers’ blood samples (t=−10.46, P<0.001), except the 207/206Pb between workplace dust samples and workers’ blood samples (t=−0.12, P=0.912). In the patients afflicted with lead poisoning, the projection points of LIR of blood and urine samples from the same individual were not at the same level in the two-dimensional model, nor was the LIR of urine samples before and after medical treatment of the same individual. Conclusion The optimized ICP-MS can control the RSD of main LIR (207/206Pb and 208/206Pb) below 0.20%. There are differences in the LIR distributions of different samples.

Effects of theta burst stimulation mode repetitive transcranial magnetic stimulation on negative symptoms and cognitive function in elderly patients with chronic schizophrenia / 中华行为医学与脑科学杂志

Objective:To investigate the effects of theta burst stimulation(TBS)mode repeated transcranial magnetic stimulation (r-TMS) in the left prefrontal on negative symptoms and cognitive function in the elderly chronic schizophrenic patients.Methods:Totally 48 patients with stable chronic senile schizophrenia (24 cases in r-TMS treatment group and 24 cases in r-TMS pseudo stimulation control group) were selected. The treatment group was given the TBS mode r-TMS performed in the left dorsolateral prefrontal cortex. The control group was given pseudo stimulation at the same site. Before and after treatment, the brief psychiatric rating scale(BPRS), scale for assessment of negative symptoms(SANS), and positive and negative syndrome scale(PANSS)were used to assess mental symptoms, while Mattis-dementia rating scale(MDRS-2)and social adaptation functioning evaluation(SAFE)were used to assess cognitive function and social function. SPSS 20.0 was used for statistical analysis.Comparisons of the differences between inter groups and intra groups were conducted by independent sample t test and paired t-test. Results:(1)There were significant differences in the total score of PANSS scale((60.17±3.73), (56.67±3.12)), the negative symptom subscale score of PANSS((20.88±2.94), (17.96±2.33)) and the score of SANS((30.67±1.66), (30.25±1.45)) before and after treatment in the treatment group (all P<0.05). The D-value before and after treatment in the scores of BPRS ( t=3.513, P=0.001), PANSS ( t=6.048, P<0.01), negative symptom subscale ( t=6.610, P<0.01) and SANS ( t=8.239, P<0.01) were significantly different between the two groups. (2)There were significant differences in the scores of MDRS-2 and its sub scales before and after treatment in the treatment group (all P<0.05). The D-value before and after treatment in the scores of MDRS-2 ( t=6.216, P<0.01), attention ( t=4.596, P<0.01), start/maintain ( t=6.424, P<0.01), concept formation ( t=3.974, P<0.01), construction( t=2.194, P=0.033) and memory ( t=3.162, P=0.003) were significantly different between the two groups.(3)There was no significant difference in the SAFE score between the treatment group and the control group before and after treatment ( t=0.138, 0.142, both P>0.05). Conclusion:TBS can improve the negative symptoms and cognitive function in patients with the elderly chronic schizophrenic, but the effect of social function is not clear.

Parameterized Analysis of Craniocerebral Injury Caused by Fist / 法医学杂志

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.

[Economical nitrogen application rate of winter wheat under rice-wheat rotation in the Yangtze River basin of China]. / 长江流域稻麦轮作条件下冬小麦适宜施氮量.

To promote the rational application of nitrogen fertilizer for winter wheat under rice-wheat rotation in the Yangtze River Basin, we examined the effects of nitrogen application rates (0, 120, 210, 300 kg·hm-2, expressed as N0, N1, N2, and N3 respectively) on soil nitrate content, nitrogen balance of soil-plant system and yield. The results showed that soil nitrate content increased with increasing nitrogen application rates. Under different nitrogen application treatments, all the nitrate was significantly transfered to the 60 cm soil layer till jointing stage. After jointing stage, topdressing nitrogen significantly increased nitrate content in 0-40 cm soil layer under N1 and N2 treatments and that in the 0-60 cm soil layer under N3 treatment. Soil nitrate mainly accumulated in the 0-40 cm soil layer in the mature stage. Results from nitrogen balance analysis showed that nitrogen absorption, residue and loss varied across different growth stages of wheat, with the period from overwintering to jointing being the principal time of apparent nitrogen loss. The amount of plant nitrogen accumulation, inorganic nitrogen residue and soil nitrogen apparent loss all positively correlated with the nitrogen application rate. Based on the comprehensive analysis through Coase principle and marginal revenue of environmental economics, the optimum nitrogen application rate for production, ecology and economic benefits of winter wheat under rice-wheat rotation was 250 kg·hm-2, and the ratio of base fertilizer to jointing fertilizer was 5:5, while the corresponding grain yield was 6840 kg·hm-2.

[Characteristics of uptake, residual and loss of nitrogen fertilizer in winter wheat after rice stubble]. / 稻茬冬小麦氮肥吸收、残留和损失特性.

To promote the rational application of nitrogen fertilizer in winter wheat after rice stubble, the effects of nitrogen application rate (0, 150, 225, 300 kg·hm-2, expressed as N0, N150, N225, N300) on nitrogen recovery, residue, loss and grain yield were examined using field 15N tracer technology. The results showed that with the increases of application rate, nitrogen accumulation from different sources significantly increased while nitrogen recovery significantly decreased. The accumulation of basal nitrogen in plants reached the peak during overwintering stage to jointing stage, while the accumulation of topdressing nitrogen peaked between jointing to flowering stage. At maturity, nitrogen accumulation of the top fertilizer was higher than that of the base fertilizer. Plant nitrogen accumulation from soil under N150 was higher than that from nitrogen fertilizer, but with an opposite tendency under N225 and N300. With the increases of nitrogen application rate, the residual nitrogen in the 0-100 cm soil layer in the maturing stage significantly increased, while the residual nitrogen ratio in the 60-100 cm soil layer gradually increased. In the whole growth period of wheat, both nitrogen loss and loss ratio were positively correlated with nitrogen application rate. The nitrogen loss of base fertilizer reached the highest during sowing to overwintering stage, while the nitrogen loss of top fertilizer was at the peak from jointing to flowering period. Taking grain yield into consideration, N225 treatment was the proper application rate for winter wheat after rice stubble, with grain yield being 6735 kg·hm-2, and the nitrogen fertilizer recovery rate, soil residue rate and loss rate being 42.6%, 34.0% and 23.3%, respectively.

Research Status of Postmortem MSCT Angiography in Forensic Science / 法医学杂志

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.

Research Progress on Estimation of Postmortem Interval Using mRNA and ncRNA / 法医学杂志

Postmortem interval （PMI） estimation has always been an important and difficult issue in the field of forensic pathology. In recent years, research progress on the estimation of PMI using RNA specific variation patterns after death has been made by researchers at home and aboard. This paper summarizes the specific application methods of messenger RNA and non-coding RNA for PMI estimation based on the literatures and discusses the existing problems and development trends, in order to provide technical reference for related studies and estimation practice.

Analysis of Influencing Factors of Single Camera Photogrammetry in Forensic Three-Dimensional Reconstruction / 法医学杂志

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.

Application of Artificial Intelligence Automatic Diatom Identification System in Practical Cases / 法医学杂志

Objective To discuss the application of artificial intelligence automatic diatom identification system in practical cases, to provide reference for quantitative diatom analysis using the system and to validate the deep learning model incorporated into the system. Methods Organs from 10 corpses in water were collected and digested with diatom nitric acid; then the smears were digitally scanned using a digital slide scanner and the diatoms were tested qualitatively and quantitatively by artificial intelligence automatic diatom identification system. Results The area under the curve （AUC） of the receiver operator characteristic （ROC） curve of the deep learning model incorporated into the artificial intelligence automatic diatom identification system, reached 98.22% and the precision of diatom identification reached 92.45%. Conclusion The artificial intelligence automatic diatom identification system is able to automatically identify diatoms, and can be used as an auxiliary tool in diatom testing in practical cases, to provide reference to drowning diagnosis.

Evaluation of 3D Measuring Methods for Body Surface Damage and Scars / 法医学杂志

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.

Exploring of the Mechanism of Rib Fracture Caused by Landing on Different Parts of the Trunk after Falls from Height Using Finite Element Method / 法医学杂志

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.

Observing and detecting on blood flow in hepatic sinus in hepatic steatosis mice / 解剖学报

Objective Due to the distortion of hepatic cells in hepatic steatosis, the characteristics of blood flow in the liver could change. This study observed the morphology, blood flow velocity and tortuosity changes aimed to help the diagnosis and treatment in the hepatic steatosis. Methods The hepatic steatosis model was established by subcutaneous injection of carbon tetrachloride (CCl4) and olive oil in mice, and then liver tissue was stained with HE and oil red 0 staining. Laser ultrasound was used to measure the blood flow changes in the superficial hepatic vessels of the left lobe. The mice's tail veins were injected with Texas red fluorescent dye, then two-photon fluorescence microscopy were used to detect the flow of red blood cells in mice's hepatic sinusoids, blood vessel diameter, the hepatic sinusoidal tortuosity. Results After injected with CCl4 for two(n= 16) or four(n= 16) weeks, the oil red 0 staining indicated lipid accumulation in hepatic cells, especially around the central vein. HE staining indicated narrowing of the hepatic sinusoidal vessels, and more obviously in 4-weeks group. As the modeling time increased, the blood flow velocity decreased gradually in hepatic sinusoids and superficial hepatic vessels in the left lobe, and the diameter of the hepatic sinusoids became smaller. Conclusion In the hepatic steatosis, the internal diameter of hepatic sinus decreases, and the blood flow also decreases in the hepatic sinusoids, but hepatic sinusoidal tortuosity increases. All of this provide a visual morphological experimental basis for the early diagnosis and treatment to the hepatic steatosis.

Research Progress on Postmortem Changes of Computed Tomography Imaging Characteristics on Corpses / 法医学杂志

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.

Quantitative Expression of RNA from Frozen Organs and Formaldehyde-fixed and Paraffin-embedded Tissues / 法医学杂志

Objective Quantitative analysis and comparison of the expression of ribonucleic acid （RNA） from frozen organs and formaldehyde-fixed and paraffin-embedded （FFPE） tissues. Methods Frozen specimens of human brain, myocardium and liver tissues as well as FFPE samples at different postmortem intervals were collected and mass concentration of RNA was extracted and detected. Reverse transcription-quantitative polymerase chain reaction （RT-qPCR） technology was used to analyze the amplification efficiency and relative expression of each RNA marker. Results The mass concentration and integrity of RNA extracted from FFPE samples were relatively low compared with frozen specimens. The amplification efficiency of RNA markers was related with RNA species and the length of amplification products. Among them, glyceraldehyde-3-phosphate dehydrogenase （GAPDH） and β-actin （ACTB） with relatively long amplification products failed to achieve optimal amplification efficiency, whereas 5S ribosomal RNA （5S rRNA） achieved ideal amplification efficiency and showed quite stable expression across various tissues, therefore it was chosen as internal reference marker. The expression quantity of GAPDH and ACTB in frozen specimens with longer postmortem intervals and in FFPE samples with relatively long amplification products was decreased. The expressions of tissue-specific microRNAs （miRNAs）, GAPDH and ACTB with relatively short amplification products had consistency in the same tissues and FFPE samples. Conclusion Through standardizing the RT-qPCR experiment, selecting the appropriate RNA marker and designing primers of appropriate product length, RNA expression levels of FFPE samples can be accurately quantified.

Research Progress in Virtopsy of Drowning / 法医学杂志

Dead bodies found in the water are not all caused by drowning. The important task of forensic identification is to distinguish between entering the water before and after death, and to clarify the cause of death. In the practice of forensic identification, drowning is generally diagnosed on the basis of comprehensive considerations such as cadaveric signs, histopathological examinations, and diatom tests, with the exclusion of other causes of death. The emergence of virtopsy techniques provides new insights for the diagnosis of drowning. This paper reviews the post-mortem imaging studies of sinus and mastoid small chambers, respiratory tracts, lung tissues, gastrointestinal tracts and blood in the corpses in recent years. The value, potential of virtopsy in the diagnosis of drowning is discussed, with the prospects of its development direction.

Characteristic Changes and 3D Virtual Measurement of Lung CT Image Parameters in the Drowning Rabbit Model / 法医学杂志

OBJECTIVES@#To use virtual anatomy technique in the analysis of post-mortem characteristic changes of CT images in the experimental drowning rabbit model and the related parameters in 3D virtual model, so as to explore its application value in the diagnosis of drowning in forensic pathology.@*METHODS@#A model of drowning rabbits was established, with animal models of hemorrhagic shock and mechanical asphyxia as the controls. CT scan was performed on the experimental animals, and the differences in imaging features between the groups were compared by morphological reading of the tomographic images. CT data were imported into Mimics 14.0 software for 3D modeling. The CT values and lung volumes were calculated by the software, and the differences on CT values and lung volumes brought by different causes of death were analyzed.@*RESULTS@#The CT images of lungs in the drowning group showed characteristic ground-glass opacity （diffuse and uniform density increase）. There were no obvious abnormalities in hemorrhagic shock group, and only a few similar changes were found in the mechanical asphyxia group. Compared with the controls, the CT values and the lung volumes in the drowning group were significantly increased P<0.05.@*CONCLUSIONS@#Based on post-mortem lung imaging, the combination of CT value and lung volume changes can effectively reflect the virtual anatomical features in drowning, and provide a diagnostic basis for the forensic identification of drowning.

Methodological research of RNA extraction and quantitative analysis of long non-coding RNA from formalin-fixed paraffin-embedded human brain specimens / 上海交通大学学报（医学版）

Objective·To compare the quality of RNA extracted from fresh and formalin-fixed paraffin-embedded (FFPE) brain tissues and to explore the long non-coding RNA (IncRNA) expression level.Methods·FFPE samples stored under various conditions and paired frozen brain tissues were collected and total RNA qualities were then detected.Amplification efficiency (AE) and expression stability of each RNA marker were calculated and analyzed based on real-time quantitative PCR.After selecting reference biomarkers,normalized △ Ct values of candidate makers within different amplicon size were measured to assess the possibility of lncRNA quantification in FFPE tissues.Results·The purity of RNA extracted from FFPE was relatively high,but the RNA integrity was lower than fresh samples.All biomarkers were successfully amplified and amplification efficiencies of long-chain RNA markers were correlated with amplicon sizes,sample treatment and preservation conditions,namely temperature and storage time.5S,miR-9 and miR 125b achieved optimal AE and showed quite stable expression in all specimens,therefore they were chosen as control markers.Compared with fresh samples,the △ Ct values of only 2 lncRNA (HAR1F and MALAT1-L,whose amplicon size were both higher than 200 bp,respectively) increased in the FFPE samples kept in 4 ℃,while in FFPE tissues kept in room temperature,increments of the △ Ct values were significant for most target genes except for short amplicon markers (＜60 bp),which showed consistently stable expression in all brain specimens.Conclusion·RNA integrity is affected by sample treatment and preservation conditions,but IncRNA expression levels in FFPE tissues can be accurately quantificated by using optimal amplicon sizes and considerable reference markers.

Diagnostic Value of Postmortem CT Angiography in Coronary Atherosclerosis / 法医学杂志

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.

Reconstruction of Vehicle-human Crash Accident and Injury Analysis Based on 3D Laser Scanning, Multi-rigid-body Reconstruction and Optimized Genetic Algorithm / 法医学杂志

Objective To reconstruct a vehicle-bicycle-cyclist crash accident and analyse the injuries us-ing 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-ob-jective 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. Re-sults 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 ve-hicle 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. Conclusion 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 opti-mized genetic algorithm, which have application value in the identification of injury manner and analysis of death cause in traffic accidents.

Research of clinical values of general intervention in medication management of elderly patients with hypertension / 中国生化药物杂志

Objective To analyze and explore the clinical value of nursing intervention service in the medication management of elderly patients with hypertension. Methods 120 cases of elderly patients with hypertension and who received in Putuo Hospital of Zhejiang were collected and were randomly divided into two groups: The control group of 60 patients were given the conventional antihypertensive treatment, while the nursing group of 60 patients were given the nursing intervention on the basis of the reference group. Then, the medication management and blood pressure control of two groups after the intervention for six months were observed and compared. Results The medication knowledge, medication compliance and medication management level after the intervention in the nursing group were significantly higher than those in the control group (P<0.05); The blood pressure control rate after the intervention in the nursing group was significantly higher than that of the control group (P<0.05). Conclusion The nursing intervention service for elderly patients with hypertension which can effectively improve the management effect and blood pressure control rate, thus it is worth learning.