Objective To examine the method of least-square fitting for calibrating the palatal rugae boundary. Methods According to the distribution of the teeth, the feature points were selected; when they were fit, the boundary of the palatal rugae area was created, thereby constructing a mask. The mask was used to remove the part located outside the boundary and filter out the interference. Three samples were utilized for the ex-periments and analyses to come. Results To evaluate the quantitative results of the fitting curves, the correla-tion coefficients(r)of the samples and the relationship between the actual mean value and ideal mean value was obtained through six fitting processes. The differences between the actual mean and ideal mean were found to be significantly small (from 0.2857 to 2.5000) in the six fitting processes, with the range of r close to 1(from 0.9896 to 0.9995). Conclusion The effect of the cubic polynomial fitting method adopted in this study was stable.The proposed boundary calibration method can effectively locate the palatal rugae boundary and remove the interference area, further promoting the practice of forensic identification.

Objective To collect cases of non-violent death occurred in custody for analyzing the forensic characteristics and related influencing factors.Methods Sixty-three cases of non-violent death among detainees in custody that handled by a forensic science center from 2000 to 2015 were collected.The type,onset season,medical history,clinical manifestation,treatment and duration of related fatal diseases were analyzed retrospectively.Results The deaths due to diseases in custody were common in male,and with a high incidence in middle aged adults.The most common cause of death was cardiac death (50.8％).Chronic inflammatory diseases such as gastrointestinal perforation,pulmonary tuberculosis,pneumonia,hepatitis and pancreatitis,were common.There was a peak incidence in summer.The acute symptoms included sudden onset during sleep and sudden apsychia,and emesis,abdominal pain,fatigue,chest tightness,shortness of breath,fever and anorexia were the most common chronic symptoms.Conclusion The management system,custody condition,medical level and rescue rudiment of custody still need improvements.It should be pay more attention to collecting the information of medical history,autopsy,histological examination and toxicological analysis,etc.

Objective To establish a method for the analysis of methcathinone in urine by gas chromatography-mass spectrometry (GC-MS).Methods Proadifen hydrochloride (internal standard) and buffer solution (pH=9) were added into the urine samples,and methcathinone was extracted by ethyl acetate.The extract was volatilized in 50 ℃ nitrogen gas flow and the remnant was dissolved by methanol and analysed by GC-MS.Results The methcathinone in urine showed a good linear relationship in the mass concentration range of 0.02-2.00 μg/mL.The linear equation was y=0.301 9x+0.0189 (r=0.9992),and the detection limit was 0.01 μg/mL.The recoveries of methcathinone in urine was 96.4％-99.2％,with the intraday precision of 5.8％-7.6％ and the inter-day precision of 6.0％-8.1％.Conclusion The method is convenient and sensitive,which can be applied to the forensic identification of methcathinone in urine.

Objective To explore the applied value of electroencephalogram (EEG) in assessment of psychiatric impairment among patients with mental disorders due to traumatic brain injury.Methods According to the ICD-10,a total of 271 subjects were enrolled and assessed with the criterion of mental disorders due to traumatic brain injury.Activity of Daily Living Scale (ADL),Functional Activities Questionnaire (FAQ) and Social Disability Screening Schedule (SDSS) were used to evaluate the severity of patients.All the participants were tested by Wechsler Adult Intelligence Scale (WAIS) and examined by EEG.Results Totally 215 patients accomplished the study.The results of Glasgow Coma Scale (GCS),the severity of craniocerebral injury and the scores of FAQ,SDSS and ADL showed significant difference among the patients with different severity of EEG (P＜0.05).The grades of psychiatric impairment showed significant difference among the patients with different abnormal EEG (P＜0.05).Conclusion EEG can reflect the severity of craniocerebral injury,assist evaluate the social function and activity of daily living of patients with mental disorders due to traumatic brain injury,and distinguish the mild psychiatric impairment grades,which suggest that EEG has a certain reference value in the assessment of psychiatric impairment.

Objective To establish a convenient and rapid method for extracting DNA from bone.Methods Fifteen long bone samples were washed and sterilized.The skeletal fragments were obtained by electric drill,and lysed by PrepFiler Express BTATM lysis buffer.DNA was then manually extracted by silicon microbeads for further analysis.Results STR genotyping was successfully obtained in 14 out of the 15 samples,and the detection rate was 93.33％.Conclusion The method for DNA extraction from bone established in present study is convenient,quick,effective,and with a strong applicability,which is worth spreading and applying.

Objective To explore the correlation between the imaging parameters of skull and the external features of eyes.Methods Positive images of the head face and the frontal and lateral X-ray films were obtained from 101 cases of adult males of the Han nationality aged from 20 to 40 years old in Northeast China.The face width (x1),upper face width (x2),biorbital width (x3),all facial height (x4),upper facial height (x5),maximum breadth of skull (x6),minimum breadth of frontal bone (x7),orbital width Ⅱ (x8),anterior interorbital breadth (xg),maximum height of skull (x10),minimum width of nasal bone (x11) and orbital height (x12) were measured and the data were statistically analysed.Results Through the linear regression analysis,the regression equations of the presumed inboard canthi (y1) and outboard canthi distances (y2) were established,respectively,which were y1=0.025 x2+0.291 x3-0.011 x7+0.041 x10-0.525(R=0.613,SEE=0.222 cm) and y2=1.703-0.08x2+0.573 x3-0.142x4+0.421 x5+0.096x7-0.256x8+0.149x9+0.071x10(R=0.745,SEE=0.341 cm).The back-substitution check showed that the accuracy rate of two equations at ±1SEE were 75.2％ and 80.2％,respectively.Conclusion The established regression equations of external features of eyes have high estimation accuracy,which can be used to the practical work of facial reconstruction.

Objective To explore the application value and forensic significance of ischemia modified albumin (IMA) in pericardial fluid to diagnose sudden cardiac death.Methods IMA level in pericardial fluid was detected in acute ischemic heart disease group (n=36),acute myocardial infarction group (n=6),cardiomyopathy group (n=4) and control group (n=15) by albumin cobalt binding method.The levels of IMA were compared among these groups.The best cut-off IMA value was estimated and the sensitivity and specificity of acute myocardial ischemia group was distinguished from control group by receiver operating characteristics (ROC) curve.Results The IMA level in acute ischemic heart disease group was significantly higher than that of control group (P＜0.05).Compared with acute myocardial infarction group and cardiomyopathy group,the IMA level in acute ischemic heart disease group had no significant difference (P＜0.05).The cut-off value for the identification of acute myocardial ischemia which obtained by ROC analysis was 40.65U/mL.And the sensitivity and specificity for distinguishing acute ischemia cardiac disease was 60.0％ and 80.5％,respectively.Conclusion The IMA value in pericardial fluid can be a reference marker for the diagnosis of acute myocardial ischemia,which also can provide objective basis for the forensic identification of sudden cardiac death.

Objective To analyse the cases of sudden death due to hyperthyroid heart disease,and explore the general information of deaths and the forensic pathological characteristics to provide reference evidence for forensic identification of such cases.Methods Six cases of sudden death due to hyperthyroid heart disease between 2001 and 2016 were selected from School of Forensic Medicine,China Medical University.The general information (gender and age),clinical manifestations,medical history,anatomical and histopathological findings,biochemical parameters and cause of death were analysed retrospectively.Results Most of the 6 patients had definite history of hyperthyroidism,and they all showed certain degrees of symptoms of cardiovascular disease;had obvious incentive factors of death;histopathological examination of thyroid conformed to the performances of diffuse toxic goiter;with increase of cardiac weight,dilatation of cardiac chambers,myocardial hypertrophy and focal necrosis;postmortem biochemical analyses of pericardial fluid could be used as an additional method for diagnostic of sudden death due to hyperthyroid heart disease.Conclusion The identification of death due to hyperthyroid heart disease should be based on the clinical history and the results of autopsy,histopathological examination,postmortem toxicology tests.The postmortem biochemical detection of thyroid and cardiac function should be performed if necessary.

Sudden death (SD) is a special kind of death owing to disease,which severely threatening the lives of community population.As the most common type of SD,sudden cardiac death (SCD) has always been a crucial content of identification and research in forensic pathology.This article reviews the research progress from the aspects of epidemiology,morphology,molecular pathology and virtual anatomy of SCD in forensic medicine,so as to provide a reference for the morphological identification,determination of cause of death,and integrated control of this kind of SD.

Olfaction is one of the basic feelings,which plays an important role in appetite,warning of danger and emotion regulation,etc.More and more studies have shown that olfactory dysfunction may affect quality of human life.Thus,the attention of olfactory dysfunction is increasing.There are many subjective and objective methods for olfactory function detection,and olfactory event-related potential (OERP) is a more objective method.This article reviews the development,testing and analysing methods and clinical research of OERP,and explores its application prospects in forensic clinical medicine.